Archive | Cranks

12-Speed Rene Herse Cranks

We’re excited to announce that our ramped-and-pinned chainrings are 12-speed compatible. We knew that 12-speed was coming when we developed our 11-speed rings, so we tried to anticipate the requirements, so that our chainrings would be compatible with 12-speed as well.

Now we’ve completed our testing, and we’re happy to report that all our ’11-speed’ chainrings also work well with 12-speed chains. Continue Reading →

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Why Square Taper Bottom Brackets?

Square taper bottom brackets may seem like anachronisms dating from the last century, and yet they remain the best option for metal cranks. Here is why our Rene Herse cranks use square tapers and will continue to do so in the future.

Modern bottom brackets have larger spindles, so they can use thinner walls. The result is a lighter bottom bracket – but the larger spindle requires more material on the crank.

No problem on a carbon crank (above), which needs to be large anyhow, because carbon is very light, but also bulky. Just don’t try to replicate the massive shape of a carbon crank in aluminum: It will get very heavy.

Our Rene Herse cranks are so incredibly light – just 490 grams for the 42/24 shown above – because they use only as much material as necessary. We’ve optimized the shape using Finite Element Analysis to remove all material that isn’t needed, but keeping aluminum where it’s needed for strength. The photo above shows that there is just enough material to fit a slender square taper spindle. Imagine how much material we’d have to add to make room for a massive spindle!

The light weight doesn’t come at the expense of durability or safety: Our cranks pass the most stringent EN ‘Racing Bike’ test for fatigue resistance. Few other aluminum cranks are as light and as strong.

There is another benefit of square tapers: The taper reforms itself every time you install the crank. You can remove and install the cranks dozens (or hundreds) of times, yet the square tapers will not develop play. And even if a crank comes loose by accident because the crank bolt wasn’t tightened enough, you can usually reform the taper: Tighten the crank bolt as much as you can, then ride the bike for 5 miles, retighten the bolt, etc. Do this five times, and the taper will usually be fine, unless it’s really been damaged beyond repair.

The smaller spindle of a square taper has another advantage: It leaves more room for the bearings. Above is an SKF bottom bracket that I cut open after years of use. The large ball in the center shows the size of the balls used in the SKF bottom bracket. On the right is a typical, much smaller, ball from a modern bottom bracket.

Bike makers now work around that problem with new standards that use bigger bottom bracket shells. For carbon frames, this works fine, since you have a lot of material in the BB region anyhow. A steel frame built to a ‘modern’ BB standard will be quite heavy, as the oversize bottom bracket shell adds a lot of material. Bottom bracket shells are the heaviest part of a metal frame, so keeping them as small as possible is useful for keeping the frame weight down.

And then there is the issue of the ever-changing standards, because none work as well as the old square taper. It didn’t come as a surprise when Allied, the US-based maker of high-end carbon frames, decided to return to the BSC/BSA bottom bracket standard. Their web site explains: “After more than a decade of changing bottom bracket standards, we are happily back to BSA. No more creaking, easy to service and just as light as any other bottom bracket standard. Your mechanic will thank you.”

Aren’t there performance advantages with bigger spindles? In theory, the bigger spindles are stiffer. In practice, all spindles are stiff enough. Your frame flexes far more than your bottom bracket spindle. The reason why we haven’t done a double-blind test of crank stiffness is simple: It’s so pointless that it isn’t worth the effort. Eddy Merckx used square tapers, and so do the Japanese Keirin track sprinters. If they can’t flex them, neither can you and I! In fact, I’ve raced our square taper cranks in Japan’s toughest gravel race (above) – without any issues.

It’s only for mountain biking with huge jumps – especially downhill – where the higher impact strength of larger spindles is useful. That is why we don’t recommend Rene Herse cranks for mountain bikes. On the road, cranks don’t fail due to impact, but they fatigue after many miles of use. To resist those forces, we forge our cranks. This aligns the grain structure to make them more resistant to fatigue.

We give a 10-year warranty on our Rene Herse cranks as well as on our SKF bottom brackets. Few makers are prepared to stand behind their products for that long. This illustrates how much confidence we have in our square tapers (and the rest of our cranks and bottom brackets). We’ve spared no expense to make them as good as they could possibly be.

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48/33 Rings for Rene Herse Cranks

We’re offering a new chainring combination for our 11-speed compatible Rene Herse cranks. The 48/33 is a perfect size for fast-paced group rides – you won’t get dropped even on downhills with a tailwind, yet the 48 is a bit smaller than the more common 50, allowing you to stay in the big ring on most hills. And if it gets really steep, the 33 extends your range down to a 1:1 gear with most cassettes – or beyond.

This is the combination that I ride in Paris-Brest-Paris, where strong tailwinds and fast groups can require slightly bigger gears than we use during our adventures in the Cascade Mountains.
Why the 15-tooth step between chainrings rather than the more common 16-tooth? To understand why a 48/32 doesn’t work well, let’s look at how ramped-and-pinned chainrings work.

The pins pick up the chain and lift it onto the big ring. The ramps only make room for the chain, so it can smoothly climb onto the big ring; they don’t actually lift the chain.
Chains are made of ‘inner’ and ‘outer’ links. The pins on the large chainring work only if they mesh with an ‘outer’ chain link, right in the middle of the link (above). Inner links are recessed and won’t touch the pin.
The problem with a 48/32 is that both tooth counts are divisible by 16. This means that there are 16 possible positions for the pins. The bad news is that those 16 positions always hit the same chain link – either an inner or an outer – depending on how the chain is placed on the chainring. If the pins always hit inner links, they won’t help with the shifting at all.
In other words, the 16 possible pin positions on a 48/32 ring are duplicates. What you need are (at least) two distinct positions, so there’s always a pin that hits an outer link – no matter how the chain goes on the ring.

That is why we make a 48/33, where the pins always line up with outer (and inner) chainlinks, no matter how the chain is placed on the ring. That is how all ramped-and-pinned chainrings work: Half the pins don’t do anything, but the other half pick up the chain reliably. It doesn’t matter how the chain is positioned on the chainring – half the pins line up correctly.
Now you can see why ramped-and-pinned chainrings only work in pairs. That is why the big ring is marked not just with its own tooth number, but also with the small ring size for which it is designed.
Some makers offer rings that just have a few ramps and pins, without a clearly designed path for the chain. Usually, they are marked only with their own size. Those rings still shift OK – the same as classic chainrings. It’s just that those ramps and pins don’t really do much… and with narrow 11-speed chains, it gets harder to lift the chain to the big ring without the help of a pin.

With the new chainrings, Rene Herse cranks are the only 11-speed compatible cranks with a full range of customized gearing: 48/33; 46/30; 44/28; 42/26. It’s great to have those gearing options, whether you want the new 48/33 for fast group rides or the 42/26 (above) for mountain adventures. We have you covered. And you’ll get shifting that rivals the very best from the big makers, plus superlight, forged arms that pass the most stringent EN ‘Racing Bike’ fatigue test.

If you bought a Rene Herse crankset in the past, you’ll like that all our cranks (since we introduced them in 2011) are easy to convert to 11-speed. All you need is a new 11-speed large chainring. We designed the new rings so they work with our existing small rings and crankarms. Because we don’t believe in planned obsolescence, and we are committed to supporting our products in the long run.
Click here for more information about Rene Herse cranks.

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Longer cranks should be stronger

Our Rene Herse cranks are available in three length: 165, 171 and 177 mm. We chose 3.5% increments, because that is the smallest difference you’ll notice as you ride. That part is just common sense. What makes our cranks unique among small-production cranks is that we use different forging dies for each crank length.

Let’s first talk about why we forge our cranks: Forging strengthens the metal because it aligns the grain structure (above). By contrast, CNC machining just carves the part out of a big block of aluminum. You’ll still have the grain structure of the original block, which is now interrupted where the block has been cut away. On a complex shape like a crank, this creates a lot of weak spots. (Aluminum behaves a lot like wood in this respect, where you always want to work with the grain, not cut across it.)
To make up for the lack of strength, CNC-machined parts use more material, making them bigger and bulkier. If you want slender, lightweight parts that still are strong enough for hard riding, you’ll want to forge them.
To obtain the full advantages of forging, the forging die must be close to the final shape of the crank. Otherwise, you start cutting into the grain structure again, and you lose the strength advantages of forging. That is why Rene Herse cranks use different forging dies for each crank length. Above you see the raw forgings. To turn them into cranks, holes are drilled and threaded and the arms are polished. The grain structure of the cranks remains uninterrupted.

Forging dies are expensive, and that is why small makers either CNC machine their cranks or, if they forge them, often use a single forging for all their crank lengths (above, the final forging is at the bottom). The area where the pedal eye will be is elongated, so that the crank can be machined to the final length as needed. This saves money, but it means that the forging’s grain structure is interrupted in the highly-stressed area at the transition to the pedal eye, where many cranks break. Does it matter?
Years ago, the then-owner of TA told me that in the past, they had two forging dies for their cranks. Back then, most riders used 170 mm cranks, so they made a net-shape forging for that length, similar to the Rene Herse forgings above. This made sense, because it eliminated the machining, which was expensive in those pre-CNC days. But there was an added benefit: Very few of these cranks broke.
For the other arm lengths – and TA used to offer many – demand was not enough to warrant a net-shape forging die for each length, so they made the forging with the oblong pedal eye that you see above. This was then machined to the final shape. According to the owner of TA, those cranks were less reliable.

This matches my experience. Recently, I encountered a broken crank (above). Checking the length, I wasn’t surprised that it was a 177.5 mm crank. When I traced the shape of the raw forging on a piece of paper, I could see that the crank broke exactly where the oblong pedal eye started on the original forging, and where the material was removed. It makes sense – this is the most stressed area, because the pedal has the most leverage here.
This doesn’t mean that all cranks that don’t use net-shape forgings will break. Note the oxidation on the broken crank – it’s seen a lot of miles, and it was used on a commuting bike, where lots of starts and stops put great strain on the crank. Still, I sleep better at night knowing that Rene Herse cranks don’t have that weak spot.

When we developed our Rene Herse cranks, we decided that they had to be as strong and as reliable as the best cranks in the world: Our cranks had to pass the EN ‘Racing Bike’ standard, not the less-demanding ‘Trekking/City Bike’ standard that most other small-production cranks meet. The only way to pass that rigorous test is by using net-shape forgings, which require dedicated forging dies for each crank length.
Using separate forging dies for each crank length has one added advantage: We can make the longer cranks stronger. If you look carefully, you can see that the arm on the left has a larger cross-section. This compensates for the longer lever of the 177 mm cranks and also for the higher power output and greater weight of taller riders. It’s logical, yet I haven’t seen any other cranks that are beefed up for the longer versions.
This also means that all our cranks – and not just the shortest ones – pass the test. In fact, we’ve tested each length several times to be sure. (A single test might just capture a lucky outlier.)

Making separate forging dies for each crank length triples our tooling costs, but it’s the only way to make high-performance cranks that match the performance and reliability of the best cranks from the big makers, while still offering unlimited chainring choices and an understated classic aesthetic. You don’t make the world’s best components by cutting corners!
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Rene Herse 11-speed Chainrings in New Sizes

Chainrings choice. It’s one of the main attractions of our Rene Herse cranks – together with light weight, supreme reliability and, dare we say it, good looks. So when we presented our first 11-speed chainrings, it was only a matter of time until the program was expanded. Now we are introducing our 42/26 and 44/28 chainrings, which complement the 46/30 rings already available in our program.
More than two years ago, we asked our chainring suppliers about 11-speed chainrings with shifting aids. Their answer was: “No problem. We can machine generic ramps into your rings and rivet in a few pins, too. We do that for many companies.”
But that was not what we had in mind: We didn’t want ramps and pins that are more cosmetic than functional, and don’t really help with shifting. As with all our parts, we wanted our 11-speed chainrings to equal the performance of the best in the business.
That was the start of our most ambitious R&D project to date. Since that first conversation, it has taken more than 2 years, hundreds of engineering hours, dozens of computer models, and thousands of testing miles.
As always, our first step was to research what others had done. It soon became obvious that only the very largest component makers have developed well-shifting ramps and pins. Understanding their thinking allowed us to come up with improvements and modifications that would make our rings work at least as well as theirs, while preserving the shape and interchangeability of our Rene Herse rings.
After we had developed our new chainrings in concept, we printed models on our 3D printer. These rings weren’t strong enough for riding, but they allowed us to visualize how our ideas work in practice.

Then came the big step: Commissioning prototype chainrings – easily recognizable by their unpolished surface. The complex shape of the teeth requires a 5-axis CNC machine, so we can’t make them in-house. As one-offs, they are very expensive, so we had to be sure of our design before we ordered them. Fortunately, they worked as well as we had predicted. I rode them for a few thousand kilometers last year, including in the Volcano High Pass Challenge and at the Bicycle Quarterly Un-Meeting. I’m happy to report that they really do perform as well as the best rings you can get from the big makers.
After we introduced the 46/30 rings, we continued developing the other sizes. Each ring is a separate project, and each ring is designed to work only with a single inner ring: The teeth of both rings must line up in a particular way to get a good shift. The pin must hit the chain in the middle of a link and not at the pivot, otherwise, it doesn’t really do much to lift the chain. And then the chain must mesh seamlessly with the teeth of the big ring. That part is actually the hardest. Most makers look at the problem from a static point of view, but to optimize the shifting, you need to consider that the chainring is spinning at 90-120 rpm. The downshifts require other parts of the chainrings to be relieved, so the chain can pass to the inside without having to climb over the teeth first. There is a lot to it, and much of it is a trade secret.
What happens if you use the new rings with different inner rings? Nothing bad, it’s just that the upshifts aren’t much better than without ramps and pins. During downshifts, you’ll still benefit from the optimized tooth profiles that allow the chain to move smoothly off the big ring. (With downshifts, the chain always lands on the small ring, so it’s not important to have a matched pair of chainrings.)
I’ve been testing the new sizes over the summer on some epic rides. I’ve really appreciated the smallest combo, the 42/26 during a solstice ride around Mount Hood in Oregon. I ride it like a 1×11 most of the time, but with smaller steps between the gears. And when I need a really small gear, I shift to the small ring.

Natsuko really likes the 44/28 combination, and she can’t wait to try the new rings on her C. S. Hirose. The 46/30 is perfect for fast road riding. I use that combination on my randonneur bike. We are excited to offer all these sizes with 11-speed compatible, smooth-shifting chainrings.

The new chainrings work equally well with 10- and 9-speed. They are designed to work with all shifting systems – STI, Ergopower, DualTap, but also bar-end and downtube shifters. There is only one thing to keep in mind: They are designed to work with Shimano’s Ultegra chain. The pins have to be designed with a specific chain in mind, and we found that the Shimano Ultegra chain works best. Use the Ultegra chain that is appropriate for the number of cogs you run, and you’ll enjoy the fastest, smoothest shifting you’ve ever experienced on a bike – while running chainring combinations that perfectly match your riding style. Coincidentally, the Ultegra chain shifts better on the rear, too, no matter which cassette and derailleur you use. (On my Firefly, rear shifts became a lot crisper with the Ultegra chain, even though the bike uses Campagnolo derailleurs and cassette.)

Many of you will like that we’ve made the chainrings backwards-compatible. If you have a set of Rene Herse cranks, you can just swap the large chainring for an 11-speed one. The rest of the crank is unchanged. It’s part of our commitment to sell you only what you need, rather than forcing you to buy a complete new crankset just because you want to upgrade to 11-speed.
The new chainrings are in stock now. And as with all René Herse cranks, we offer free world-wide shipping (on Rene Herse cranks and brakes only).
Click here for more information about Rene Herse cranks.

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René Herse: The Beauty of Function

At Compass Cycles, we have taken much of our inspiration from René Herse and his legendary bikes. In the past, we’ve talked about the great performance and incredible reliability of Herse’s bikes, but what is even more striking is their beauty. You notice it immediately when you look at one of his bikes, or even a photo… but it took much study to unlock the secrets of the ‘magician of Levallois.’ (Levallois was the suburb of Paris where Herse made his bikes.)
Herse’s bikes don’t derive their beauty from complex lug shapes, but from their simplicity. It was Hiroshi Hagiwara, the maker of the Japanese Alps bicycles, who said in a recent Bicycle Quarterly interview: “A bicycle is a frame with two wheels. Everything else is a distraction.” When I thought about this while looking at a René Herse bike, I realized that Herse’s genius was to turn these distractions into assets that make the bike more beautiful.
The most obvious one are the fenders (above): They follow the outline of the wheel so gracefully that they enhance the bike to the point where the same bike without fenders would look naked.

Herse masterfully joined the frame and wheels: Herse’s custom-made dropouts place the wheel centers in the prolongation of the stays and fork blades. That way, the wheels are centered in the end points of the frame, which ties the whole bike together. As an added benefit, this allows the dropouts to be smaller, stiffer and lighter.
Other things are harder to notice: The two arms of the custom-made hanger for the Cyclo derailleur line up perfectly behind each other. This is very difficult to do, since the chainstays are angled upward and outward, and the two arms have to be bent very precisely to very different curves. It adds to the beauty of the bike, even if it’s not immediately apparent.

The brake cables are truly parallel to the head tube and seatstays. That way, they don’t distract from the frame, but underline the straightness of the tubes.

Herse considered the proportions of the frame beyond the simple question of frame fit. The tandem we rode in France last summer has twin lateral stays, but they don’t just line up whichever way. Herse subtly adjusted the frame’s dimensions so that the lateral stays are parallel, and the balanced sizes of triangles they form further adds to the attractiveness of the frame.
Herse’s genius was to achieve this with bikes that also fit their riders perfectly. Because all this magic wouldn’t mean much if it detracted from the ride.

The opposite is the case. For René Herse bikes, the old adage that “What looks right usually is right” really holds true. His bikes and tandems ride wonderfully.

The beauty of Herse’s bikes makes it easy to forget that they were not intended as showpieces – they were designed to be ridden hard. Herse’s background reveals much about his thinking: He worked on prototype aircraft before he started making bicycle components and then bicycles. His aircraft experience shows in details like the custom screws: During the early 20th century, there were no universal specifications for bolts. Airplane makers made their own bolts, and to make sure that only correct bolts were used, each maker gave their bolt heads a distinctive shape. That way, a mechanic could immediately see if a bolt had been replaced with an incorrect one of suspicious quality. René Herse’s distinctive bolts for stems and seatpost binder have triangular heads that trace their origins to this practice.

Elegance and function also are combined in his lighting systems. The most important part of the photo above is what you don’t see: lighting wires. They run inside the rack, inside the fenders, and inside the frame tubes. Even where the current needs to be transmitted from the fork to the frame, there is no external wire: An insulated carbon brush on the steerer tube mates with an insulated brass ring inside the head tube, transmitting the current while allowing the fork to turn freely. Eliminating exposed wires not only is more elegant, but it also reduces the risk of wires getting snagged or breaking from being moved time and again.

The beauty of René Herse goes beyond the frames. After all, Herse started as a maker of components, and only began making complete bikes during World War II, perhaps because it was difficult to sell components without bikes onto which to put them. Herse’s components, whether his brakes (above), cranks or stems, combined superlight weight with superb performance.
Often overlooked are small details, like his double-ended bolts for attaching the rack to the brake pivots. Many builder simply use the brake bolt to hold the rack tab as well, but this brings the risk that the bolt works loose. Herse’s solution is more elegant: His brake bolt has a forward extension onto which the rack mounts with a nut. It will never work loose. You’d expect no less from an airplane builder: If a bolt loosens in mid-air, you can’t just stop and tighten it!

Despite all their elegance, René Herse’s bikes have a certain handmade quality. It’s obvious that the lugs and stem were shaped by hand. A lot of modern builders make bikes that look more crisp and uniform. At first, I thought that this was because René Herse bikes were made in significant numbers – up to 350 left the workshop during the best years – and corners had to be cut. But René Herse’s hand-lettered logo indicates that the handmade aesthetic was intentional. Herse could easily have ordered decals, but instead, every frame was hand-lettered by a sign painter. Like great pottery, Herse’s bikes look handmade without appearing crude or unfinished. In my opinion, that makes them works of art.

For the complete story of René Herse, his bikes and their riders, read our 424-page book on the ‘magician of Levallois,’ lavishly illustrated with studio photos of his bikes and historic photos from the Herse family archives. We still have a few copies of the Limited Edition (with a slipcase and art prints of four unpublished photographs from the René Herse Archives), or the ‘standard’ edition at a more affordable price (also available in French). Click here for more information.

Two of my favorite images from the book are available as large-format, ready-to-frame Limited Edition posters. Hang them on your wall and be inspired every time you look at them. Click here to order our set.
And if you haven’t seen our video of a René Herse tandem in action, click here.

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Compass 11-speed Chainrings

Compass Cycles is introducing the first-ever 11-speed-compatible René Herse cranks and chainrings. And the first-ever René Herse chainrings with ramps and pins. These are not just any ramps and pins: They’re carefully engineered to shift as well as the best cranks from the big manufacturers. We are proud to offer this performance with useful chainring sizes – plus the beauty and light weight of the classic René Herse cranks.

The shifting performance of our new cranks is a bigger deal than it may sound at first, because developing chainrings at this level is a major undertaking. Our engineering team has spent almost 18 months on this project. We tested prototypes for thousands of miles (above) before settling on a final design. (Many readers have wondered how the Firefly’s 11-speed drivetrain worked with the René Herse cranks, and why that simple question didn’t get a simple answer…)
There are plenty of ‘ramped-and-pinned’ chainrings out there, because it’s not hard to cut a few ramps into chainrings and rivet in some pins. But, the ramps and pins don’t do much unless they are carefully aligned with the chain path. To work well, the chain has to hit the pin just right, in the middle of an outer link. Then it gets transported seamlessly to the big ring, and the ramp only acts as a cut-out to provide an easier path for the chain.

Another key element is to treat this as a dynamic system, spinning at 50-130 rpm. When we looked at other chainrings, we quickly discovered that this was the biggest difference between the best-shifting chainrings and those that offer only so-so performance. It became clear that the three big makers understand this, but everybody else seems to design their chainrings as a static system. Here is what ‘static’ means: When you put a chain half on the small and half on the big ring (above), it fits beautifully. But when you shift while pedaling, the teeth don’t have time to snug in between the links of the chain (which is running at an angle during the shifts). As a result, the chain rides up on the chainring and the carefully-planned alignment of the chain path is compromised.
By comparison, the chain seems to fit a little less perfectly on the ‘dynamic’ chainrings from the big makers – until you are pedaling. Then you are surprised by the smooth shifts. We benchmarked Shimano’s Ultegra cranks – widely known as the best-shifting in the business – for the performance that our 11-speed René Herse cranks had to match. Now we feel that we have achieved that goal, and so we are introducing the first 11-speed-compatible René Herse chainrings in a 46-30 combination. And of course, the excellent shifting performance of these rings works with 10- and 9-speed derailleurs, too.

While the upshifts get a lot of attention, the downshifts are just as important with 11-speed, because the distance between the rings is so small that the chain no longer can just be ‘thrown’ to the inside and then land on the inner ring, as it was with older systems. The new René Herse 11-speed chainrings feature special tooth profiles to facilitate downshifts. The chainrings also are machined specifically to reduce the gap between the rings, so the ultra-narrow 11-speed chains cannot get caught between the rings.
Instead of requiring you to buy completely new cranks, only the outer chainring is new. What this means is that older Compass-made René Herse cranks can be retrofitted. However, the 46-30 ring should be used with a 30-tooth inner ring, otherwise, the chain path doesn’t work properly. The small chainrings remain unchanged, because they don’t do anything during shifts, except release the chain upward. Because only the outer ring is new, this also means that our 46-30 tandem cranks (below) are 11-speed-compatible, too.

The production chainrings have just arrived, so we don’t have photos yet, but rest assured that they match the beautiful finish of our other chainrings. (The photo of the ramped-and-pinned rings show unpolished prototypes.) In the future, we also plan to offer other popular chainring combinations with 11-speed compatibility.
Click here to order 11-speed cranksets or chainrings.

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Why René Herse Cranks Aren't Anodized

Sometimes, we get questions about why our René Herse cranks aren’t anodized. Some even wondered if this was a cost-saving measure. Rest assured, Compass never will choose a cheaper process over a better one. There is a reason why our cranks aren’t anodized:
When I was racing, I bought a beautiful used Campagnolo Croce d’Aune crankset (above). Named after the pass on which Tullio Campagnolo suffered from frozen fingers and no longer could open the wingnuts of his rear wheel to change gears, the Croce d’Aune group was second only to the C-Record in the Campagnolo lineup. They were a smart design and beautifully made.
The cranks had very few miles on them, as witnessed by the (then) almost-new chainrings. Even so, I paid very little for the cranks – because they had lost some of their beauty. The previous owner’s ankles had rubbed against the crankarms and worn through the anodizing. You can see it between the Campagnolo logo and the crank extractor bolt.

It wasn’t a functional problem, and since they went on a bike that I was racing hard, I didn’t care too much about the cosmetics. In fact, I soon added to that “polish” with my own ankles. The rough life of racing led to more scratches over the next few years.
And yet: if the cranks had just been polished, instead of anodized, the buffing from the rider’s ankles wouldn’t have disfigured the cranks. Even the scratches would have been easy to polish out. Polishing out scratches isn’t just about aesthetics: It allows checking whether a scratch really is a scratch, or whether it’s a crack that might cause the crankarm to break. Of course, you can polish out a scratch on an anodized crank, too, but doing so removes the anodizing, and then the crank doesn’t look good any longer.
So why do some component makers anodize their cranks? High-strength aluminum tends to corrode. Different from steel, where the corrosion flakes off until the part is gone, aluminum oxide forms a protective layer that prevents further oxidation. But it means that the aluminum turns gray. Anodizing forms a hard oxide layer that protects the alloy. Clear anodizing means that the aluminum won’t tarnish. But if the anodizing wears off in one place, the part looks worse than if it hadn’t been anodized in the first place. That is why it only makes sense to anodize components that won’t get scratched.

René Herse never anodized his cranks. The cranks on this 1952 bike still look nice after many thousands of miles. If you ride these cranks in the rain, use a high-quality car wax to protect them. That is what we do on the modern Compass René Herse cranks when we assemble them. Reapply the wax once or twice a year, and your cranks will look as nice as these, even after 65 years of hard use.

We don’t anodize our crankarms, but the chainrings are anodized. Why? They are made from 7075 aluminum for the ultimate in wear resistance. 7075 aluminum contains zinc as its main alloying agent. It oxidizes much more readily than other aluminum alloys. Without anodizing, the chainrings soon would develop ugly spots. And since your ankles (hopefully) won’t rub on the chainrings, there is little risk of wearing through the anodizing.
It would be easy to anodize our René Herse crankarms, and it would make them easier to sell, because anodizing still is taken as a sign of quality. But we prefer crankarms that we can polish and restore to “as good as new” condition, no matter how hard they have been used. Because we fully expect you to ride our cranks for many decades, just like René Herse’s riders did with their original cranks.
Click here for more information about Compass René Herse cranks.

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Choosing Your Crank Length

Our Compass René Herse cranks are available in three lengths to cover the needs of nearly all cyclists. The lengths we offer are a bit unusual, but there is a reason for this: Our cranks use dedicated forgings for each length. The “net shape forging” makes our cranks stronger than if we machined them to length. Our cranks are the only classic models that pass the most stringent EN “Racing Bike” standard for fatigue resistance.
However, this also means that we need a new forging die for each crank length. The investment is substantial. We thought hard about which lengths we need, so that nearly all cyclists would find the most biomechanically efficient cranks in our program. We selected 165, 171 and 177 mm.
Other makers may offer more lengths, but they either are huge companies (Shimano, Campagnolo) who amortize their forging dies over much larger numbers, or they machine their cranks to length (virtually all small makers). Machining the pedal eye weakens the area that is most likely to break, so that wasn’t an option for us: All Compass parts must meet or exceed the performance of the world’s best components.
We settled on three crank lengths (and three forging dies), because a millimeter or two really does not make a difference in how a cranks feel or perform. Here is how our crank lengths translate to the more common ones used by most cyclists:
For example, if you currently use a 175 mm crank, we recommend a 177 mm. It’s just 1.1% longer. (Consider that the tolerances of crank lengths are about 1 mm anyhow, so if you measured your 175 mm cranks carefully, they might actually turn out to be 176 mm long.)
It’s generally accepted that only differences of more than 5% are significant. The largest difference between the Compass René Herse cranks and the common lengths is just one-third of that threshold. Riders who’ve tried our cranks report that they cannot tell any difference compared to the lengths they used before. This means that 95% of cyclists can use Compass René Herse cranks and get the feel and performance they are used to. (Fewer than 5% of cyclists need cranks that are significantly shorter than 165 mm or significantly longer than 180 mm.)
Apart from the strength and beauty, the main thing we like about our René Herse cranks is the almost unlimited chainring choice. These days, even the big makers offer only a handful of chainring combinations. The Compass René Herse cranks allow you to get the gearing that works best for you. We offer chainrings from 52 to 24 teeth, in single, double and triple configurations, even for tandems.
For example, I use 48-32 rings for Paris-Brest-Paris, 46-30 rings for general randonneuring, and 44-28 rings for cyclotouring. They are easy to swap, if needed – you don’t even have to remove the cranks. This means that the Compass René Herse cranks can be tailored to your body and riding style more than any other crank on the market.
Further reading:

  • Blog post on how to choose your chainrings.
  • Click here to find out more about Compass René Herse cranks.
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René Herse Cranks: 177 and 165 mm

The photo above shows raw forgings for Compass René Herse cranks. Perhaps you will have spotted that they are all different: Their length varies in 6 mm steps. We introduce René Herse cranks now available in 165 mm and 177 mm lengths, in addition to the 171 mm we have offered in the past.
Why 6 mm steps? Everybody seems to agree that crank length differences of 3 mm or less are unnoticeable even for the most discerning cyclists. If you usually ride 175 or 180 mm cranks, our 177 mm will be perfect for you. The 171 mm covers 170 and 172.5 mm. And if you prefer shorter cranks, we now offer 165 mm as well. Together, these three lengths will satisfy 90% of cyclists.
Last autumn, I went to Taiwan to discuss the final phase of this new project with our suppliers. I love visiting the people who make our components. The man on the right is our engineer, who works full-time in Taiwan to supervise the production of our components that are made there. (Many other components are made in Japan, and a few are made locally in Seattle.) In the center is one of the engineers from the CNC company who machine our cranks and chainrings.
Seeing our components being made is exciting. Like most high-performance cranks, the Compass René Herse cranks are forged. It’s a very involved process: You need a huge forging hammer (above). For scale, you can see two workers in the photo. On the right you see two pallets with raw aluminum pieces that will be turned into components.
The long orange tunnel is an oven to pre-heat the parts. You heat the aluminum a little bit to make it more ductile, so it flows better when you smash it with the big hammer inside the tall machine. The “hammer” slams down onto the aluminum shape with a force of more than 1000 tons. That is the weight of 25 fully loaded semi-trucks!
The forging dies are stored in long racks. These are the tools that are smashed together, with the aluminum in between, and the result is your part. It’s that simple, except the forging dies must withstand huge forces during the forging process. No wonder they cost so much!
Why are parts forged, when the tooling is so expensive? Another process is to machine the parts, or basically carve them, out of big blocks of aluminum. To machine a part, you don’t need any specific tooling. The same milling machine that can make all kinds of things. Yet forging has two advantages:

  1. For huge production runs, forging can be less expensive. You waste less aluminum, because you only use as much as as you need for the shape of the part. (This also is better for the environment.) And forging is fast – just a second or two per part, rather than 30 minutes or more on a CNC machine. If you can amortize the cost of the forging die over millions of parts, it’s quite inexpensive. For small runs, the forging dies add significantly to the cost of each part, so CNC-machining usually is cheaper.
  2. Forging makes a stronger part. Forging reshapes the “grain structure” of the aluminum, whereas machining interrupts it. Imagine a part made from wood. If the wood grain runs the same way as your part, it will be very strong (forging). If you cut across the grain when you make the part, it will be very weak (machining).

High-end bike parts are made in small numbers, so forging is more expensive per unit. However, the higher strength means that forged parts need less material, so they are lighter and more elegant.
Most small crank manufacturers use a combination of forging and machining. The reason is simple: They want to make multiple crank lengths from the same forging die. That is a compromise, because the grain structure is interrupted right where the crank can break (at the pedal eye). When you machine a crank to length, you lose many of the advantages of the forging process.
Above you see the forging dies for the René Herse cranks. They look like negative imprints of the cranks. This is called “net-shape” forging, and it is a better way to make cranks. The advantage: You don’t machine off anything that would interrupt the grain structure. The disadvantage: You can make only one crank length from each forging die.
We use net-shape forging because it’s the only way a lightweight, classic crank meets the highest EN “Racing Bike” standards for fatigue resistance. We know that our Compass René Herse cranks are ridden hard, and we want to make them as strong as possible.
This means that for each crank length, we need a new forging die. It’s expensive, and we thought long and hard before adding new lengths to our program.
If you look carefully at the two raw forgings above, you’ll notice that we didn’t just change the length. We also added a little material to make the 177 mm cranks a bit stronger. Longer cranks have a longer lever arm for the pedaling forces. And taller riders tend to push harder on the pedals (but spin at lower cadences). Two reasons why they need stronger cranks. When you machine cranks to length, the longest cranks are also the weakest. It’s an additional disadvantage!
With net-shape forging and three raw forgings, we also need separate fixtures for each crank length, when the threads and other details are machined.
Adding new crank lengths is a large project! But it’s worth it: We want our cranks to be the best in the world. This means that we will not compromise on their performance or quality.
The new lengths aren’t the only change for the Compass René Herse cranks. We also went to a stronger aluminum. The 6066 aluminum we used until now offers great corrosion resistance and is easy to work with. That is why it’s used extensively in the bike industry. It’s also plenty strong for most riders.
However, with a superlight crank like ours, we feel more comfortable with a greater margin of safety. The 2014 alloy that we now use is stronger, yet it isn’t as brittle as the even-harder 7075 alloy that is unsuitable for bicycle cranks. (Our chainrings are made from 7075 aluminum to resist wear.)
2014 alloy is ideal for making cranks, but the heat treatment is more difficult than with other alloys. We worked with our suppliers to ensure that they mastered the process before using this alloy in our cranks. We have tested multiple samples of the new cranks, and they exceed the most demanding standards (the afore-mentioned EN “Racing Bike” standard). We are now confident to offer them to our customers.
We now have all three lengths in stock. They are available as single, double, triple, and even tandem cranks (above), with chainrings between 52 and 24 teeth. They are compatible with drivetrains from 5-speed to 10-speed.
When you enjoy the Compass René Herse cranks on your bike, you know that you aren’t just riding one of the most beautiful bike components, but also one of the best-performing. We feel that this is in the spirit of René Herse. His insistence on the highest quality and attention to detail earned him the nickname the “Magician of Levallois”.
Click here for more information about Compass René Herse cranks.

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Why Do We Make Custom Chainring Bolts?

Recently, we received our custom René Herse chainring bolts (above). Why in the world would we go through so much trouble and expense to make custom chainring bolts?
They are pretty significant little bolts, because they are the finishing touch on the René Herse cranks. René Herse chainrings are 1 mm thicker than most chainrings. This is to make them stiffer, compensating for the small bolt circle diameter. However, modern chainring bolts are designed for thinner chainrings. They are slightly domed to make their heads deep enough for full engagement with the 5 mm Allen wrench, but their edges don’t sit flush with our René Herse chainrings.
Classic Herse cranks had flush chainring bolts. We don’t know whether the “Magician of Levallois” had custom bolts made, too, or whether bolts with a thicker, flat head were available off the shelf back then. I do suspect that he would have the “correct” bolts custom-made rather than compromise. And so that is what we did.
Our new bolts have a flat surface and sit flush with our chainrings. It’s a small detail, but to us, it’s important. As custodians of the René Herse name, we have to strive for perfection…
We also offer the new bolts separately. That way, customers who bought their Herse cranks with the “domed” bolts can upgrade their cranks to the Herse bolts. The new bolts also are useful for restorations of René Herse bikes.
Click here for more information about René Herse cranks and chainring bolts.

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Small Differences Can Matter

Recently, I was on a familiar road, but riding it did not feel familiar. It seemed like I was straining to stay on top of my gear, whereas usually I just spin along. Was I exceptionally tired? I didn’t feel that way…
Then I remembered that I had replaced my 46-30 chainrings with 48-32 for Paris-Brest-Paris. In PBP, I sometimes ride in big groups and with a strong tailwind… Then my tallest gear of 46-14 – big enough for my riding in the Pacific Northwest – might not be quite tall enough.
So my big ring was 2 teeth larger than usual, hence the difficulty to stay on top of the gear. The difference is about 5% – small, but noticeable. Now that I have returned from PBP, I will re-install the 46-30 rings, since they suit my usual riding better.
It’s too bad that customizing your chainrings isn’t as easy as it used to be. Today, most makers only offer only very few chainring sizes, and none are small enough for non-racers. I have not yet been dropped because I spun out and could not keep up… and yet my biggest gear of 48-14 is 20% smaller than 50-12, the smallest maximum gear you can get from mainstream makers today.
If you have a healthy spin, you’ll rarely, if ever, use the 2 or 3 smallest cogs on a modern drivetrain. And that makes your 10-speed cassette effectively a 7-speed. With smaller chainrings, you could get a closer-ratio cassette, and have smaller steps between your gears, while maintaining the gear range that you currently use. Or you can keep your current cassette, and trade the super-large gears you never use for extra-small gears that will come in handy in the mountains.
With that in mind, we are offering dozens of chainring combinations for our René Herse cranks, from 52 to 42 teeth for the big ring, and down to 24 teeth for the small one. That way, you can equip your bike with gears that you’ll actually use!
Click here for more information about the René Herse cranks.

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Why not "Made in U.S.A."?

At Compass Bicycles, we think a lot about manufacturing. We know what we want to make, but how should we make it, and where? We are not looking for the lowest cost, but for the highest quality. The conditions under which our products are made are an important consideration as well.
There are a number of small companies who make bicycle components in the U.S., but they are often limited by the technology that is available to them. For example, CNC machines are relatively affordable and small. That is the reason why you see so many CNC-machined cranks and brakes, even though forging would make them lighter and stronger. (CNC machining is a good way to make other parts, like hubs and headsets.) CNC machining also is quite wasteful, as a lot of aluminum is turned into shavings.
In contrast, a forging hammer (photo above) is an investment that only one bicycle company has amortized on their own: Shimano is said to forge their own components. All others, including industry leaders like Campagnolo and SRAM, do not run their own forge.
The U.S. bicycle industry never specialized in making high-end components. Schwinn’s famous operation in Chicago was a self-contained factory. Rolls and bars of steel went in on one side, complete bicycles came out on the other side. Yet when Schwinn needed derailleurs or other high-end parts, they imported them from Europe. There simply were no makers of derailleurs and aluminum cranks in the U.S., and even mighty Schwinn wasn’t big enough to make their own. Very few, if any, square-taper crank have ever been forged in the U.S.A. Basically, the technology does not exist here.
Where does the technology exist? Today, the answer usually is Taiwan, which has developed a diverse bicycle industry capable of high quality, along with acceptable work and environmental conditions. Our engineer in Taiwan lives within easy motorcycling distance of the companies involved in our crank project:

  • Forge: They forge the crank blanks.
  • Machine Shop 1: They machine the chainrings tabs, square tapers and pedal threads of the cranks.
  • Machine Shop 2: They make the chainrings.
  • Screw Maker: They make our custom crank and chainring bolts.
  • Laser Cutting Specialist: They make the pedal washers.

All these companies have experience with bicycle components. Supply paths are short, and oversight is easy. Our engineer can visit the factories while production is under way, which makes it easy to solve small problems that inevitably occur when things are being made. If we made one part in Chicago, another in Texas and a third in Connecticut, this would be very difficult. (The last part of our cranks, the custom boxes, are made in the U.S.)
The Taiwanese are also willing to work with small production runs. When we asked a German screw maker about crank bolts, they told us that the minimum order was 50,000. We would have a lifetime supply of crank bolts!
The photo shows a freshly forged René Herse crank. Taiwanese workers earn good wages and work under decent conditions, comparable to North American workers. Taiwan’s environmental regulations are not as good as they could be, but they appear to be better than most countries outside Europe, Japan, and the U.S.
Many of us would like to see products made closer to home. We would like to support the economies of the places where we live. However, you need an infrastructure to make things.
Paul Krugman explained this in the New York Times: “You need a thousand rubber gaskets? That’s the factory next door. You need a million screws? That factory is a block away. This is familiar territory to students of economic geography: the advantages of industrial clusters — in which producers, specialized suppliers, and workers huddle together to their mutual benefit — have been a running theme since the 19th century.”
Unfortunately, we have been allowing these clusters to disappear all over the U.S. and Europe. In France, there was the cluster of bicycle component makers in Saint-Etienne: Manufrance, Automoto, Stronglight, Maxi-Car and dozens of other companies. Not a single one of them exists any longer!
Another cluster was Levallois-Perret in Paris with its hundreds of machine shops, chrome-platers, casters and other shops. They mostly served the automobile industry (Citroën, Delage, Hispano-Suiza, etc.), but also enabled the small constructeurs of bicycles (and the component maker TA) to do things that would have been difficult elsewhere.
These clusters no longer exist. Ernest Cuska of Cycles Alex Singer once told me how they used to have two chrome-platers within a block of the shop. Now they take their frames, racks and stems to a plater who is almost 100 miles away. TA obtains its forgings from Taiwan. So does Campagnolo. And so do we at Compass.
When you consider that our cranks and brakes are assembled right here in Seattle, perhaps we should label them “Made in the U.S.” (Legally, they are made here from imported parts.) But we aren’t trying to obfuscate, so we say that they are made in Taiwan, since most of the essential parts come from there.
And where possible, we do make products in the U.S. Our taillights, our rack tabs, the leather washers for fender mounting, our alignment tools, and our tire wipers are made by local companies and craftspeople in the U.S. And of course, Bicycle Quarterly is printed right here in Seattle.
Correction: An earlier version of this post stated that to the best of our knowledge, no square taper crank had ever been forged in the U.S. There may have been some cranks made from U.S. forgings in the 1990s (see comments).

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Supporting the Classics

When we became custodians of the René Herse name, we had three goals in mind:

  1. Bring back some of the best designs of René Herse, so that today’s cyclists could enjoy their excellent function and aesthetic.
  2. Support classic René Herse bikes with components, so that they can be kept on the road, or get restored correctly.
  3. Protect the René Herse trademark.

We like these bikes so much, and we couldn’t stand the thought that someone might exploit the name, logo and designs without respect for the heritage – with only an 80-year-old lady trying to protect her family’s life work. So we suggested to Lyli Desbois, née Herse, that she sell the rights to the name, designs, tool, etc., to somebody who could take over the custodianship of the René Herse name and heritage.*
A big step happened a few weeks ago, when our registration of the René Herse trademark was approved by the U.S. Patent Office. While the trademark and designs were protected as soon as we bought the company from Lyli Desbois and started using them again, now nobody can claim that they didn’t know the trademarks were protected. There is no risk of the René Herse logo showing up on budget frames or cheap knock-off components.
These legalities aside, we also have made progress on the other points. Our René Herse cranks have proven themselves, and many riders are enjoying not just their beauty and light weight, but also their almost unlimited chainring choices.
And owners of classic René Herses can get chainrings again for their bikes, at least for the ones made after the mid-1960s.
Now we are proud to introduce a few additional parts for classic René Herses and other cyclotouring bikes.
Early René Herse’s bike were equipped with cantilever brakes of his own design. The brake pad holders were one-piece castings, which were designed for then-common short brake pads. The short pads cleared the fork blades and chainstays when the brake was opened to remove a wheel – a nice feature.
Decades later, the short brake pads had become obsolete. When the brake pads of René Herse bikes wore out, many riders fitted Mafac pads. These pads were longer and didn’t fit in the original holders, so riders installed Mafac holders as well – as on the bike shown above. As a result, the original Herse pad holders are very rare today. And the longer Mafac pads scratch the paint every time you remove a wheel…
We now offering replacement Herse brake pad holders. We made them a bit longer than the originals, so they fits Kool-Stop’s excellent Mafac reproduction brake pads. (Unfortunately, making replicas of the original pads is too expensive at this point.) To clear the fork blades, we offset the pad slightly from the mounting post. You don’t notice it, but it provides just enough clearance to open the brake all the way. The pad holders have the same angular aesthetic of the Herse originals, and they are also cast as one-piece units for durability.
Many Herse bikes lost their wonderful straddle cable holders over the decades. We now offer replicas that allow you to complete your restoration. Of course, you also can use them on any other bike that has centerpull or cantilever brakes.
Mafac’s centerpull brakes are found not just on René Herse’s bikes, but on many other classic and modern bikes. Their performance is without par, but unless you find a set of “New Old Stock” (NOS) brakes, they’ll have seen decades of hard use. Fortunately, the arms don’t wear out, and we now offer all the other parts you need to make a set of Mafac brakes better than new. If your brakes are equipped with plastic bushings that have developed play, you can use our brass bushings to restore the performance of your brakes. (We’ll offer a tool to press in the bushings soon.) Or you can get a complete overhaul kit that replaces every nut and bolt on your brakes.
Kool-Stop now makes replicas of Mafac’s “four-dot” and “five-dot” brake pads, but with modern rubber. They are available in black and with Kool-Stop’s excellent “salmon-colored” compound (above) that offers superior braking in wet and dry conditions. We have these in stock, too.
One of the things that makes René Herse bikes special are the custom-made screws and bolts. This practice came from his aircraft background: During the early 1900s, there were no standards for bolts. Aircraft makers made their own screws to ensure they were strong enough. A bolt failure on an aircraft can have devastating consequences! The aircraft builders designed their own head shapes, so mechanics in the field could immediately see if a bolt had been replaced by a generic one of potentially inferior quality.
Drawing on that tradition, Herse made his own bolts, too. The triangular heads for his M6 seatpost binder and stem bolts are truly iconic. We now offer replicas.
We also offer the smaller M5 screws with their distinctive round heads, which Herse used to attach racks and waterbottle cages. These screws feature rolled threads, super-strong CrMo construction and durable chrome-plating. They are great not just for restorations, but also for modern bikes where you want screws that look nicer and are stronger than generic stainless steel screws.
Herse also made special bolts to attach his brakes. The rear one features a built-in washer and a much sturdier head than the thin Mafac bolts that tend to break. The front bolts (above) were even more ingenious, as they incorporated a forward extension to attach a rack.
In recent years, these bolts have been imitated by many, but never equaled. The originals incorporated a washer, and the forward extension was smaller in diameter, because the rack pushes down on the bolt and so doesn’t need as much clamping force. We now offer replicas that match the originals 100%.
Many 1940s bikes from the best French constructeurs used fender eyebolts with round heads. They are so much more elegant than the large angular heads on current eyebolts. When I restored the PBP-winning Herse tandem, one of the more tedious jobs was making the classic eyebolts and matching cups – 9 sets. (Eight for the fenders, the ninth holds the battery-powered taillight to a fender stay.) Now we offer these eyebolts in two lengths: 7 mm (stay to fender connection) and 11 mm (stay to dropout connection).
Maxi-Car hubs are my favorite hubs. With double labyrinth seals, they spin smoothly for decades. Unfortunately, they haven’t been made in 15 years, and when you find a used one, it often doesn’t have the axle length you need. To help with this situation, we offer reproduction Maxi-Car rear axles in two versions: One drilled for quick releases (left) and 140 mm long, so it can be adapted to all rear hub spacings from 115 to 130 mm.
The second version is for a Nivex-style chainrest (right). It features a stub end that is drilled to receive the wing screw that holds it to the right dropout. The stub end ensures that the axle doesn’t extend beyond the outer edge of the freewheel, so the wheel clears the chain as it is removed.
Both axles are machined from CrMo steel and heat treated, so they are even stronger than the originals.
Our final product is potentially the most useful: We asked Gilles Berthoud to re-make the Sologne panniers in a classic model. Unlike Berthoud’s contemporary version with its plastic Klick-Fix attachment that tends to rattle, the classic panniers attach with leather straps and metal springs. This provides a relatively theft-proof and secure attachment that works on (almost) any rack, provided it has a spot where the hook at the bottom can attach.
I use these panniers for all my touring, since they are waterproof and the laces allow expanding or contracting them as my luggage needs require. I have one original set that was made in 1974, yet still is going strong. Quantities are very limited, since these are specially made by Gilles Berthoud in France for us.
We hope to expand these offerings in the future. Some high-end car makers like Porsche and Mercedes-Benz offer parts and support for the classics they made decades ago. We strive to provide the same service for the wonderful bicycles of René Herse.
Click on here for more information about our classic parts.
* In 2007, I negotiated the purchase for Boulder Bicycles, who bought the name from Lyli Herse. In 2011, Compass Bicycles Ltd. bought the trademark from Boulder Bicycles.

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Meet Our Polisher

Eric Hayes is the craftsman who polishes our René Herse cranks, locally on the outskirts of Seattle. These days, most bike parts are black, and few in the bike industry still have the skills to polish metal without grinding off too much material, which looks ugly and affects the strength of lightweight parts. So we went outside the bike industry to find a polisher whose work is better than anything we’ve seen elsewhere.
Eric works with his partner Tracy in Edgewood. He polishes all types of metal. It’s hard and dirty work, but he takes great pride in his craftsmanship.
Here is a sample of his work, a hood ornament for a 1950s car. On the right, you see what it looked like when it arrived: terribly pitted. On the left is the condition after Eric finished his magic. His display includes hub caps that were dented and rusted, and now look like new. The sign with the labor rates is outdated. Eric’s rates have gone up: Skilled labor has a price.
Most of Eric’s work is for restorations of cars or motorcycles, but he does other things, too. The biggest job he’s had recently was to polish an entire private jet! Many of you have seen his work on a few bikes that have been featured in our book The Golden Age of Handbuilt Bicycles.
Here is how Eric polishes our cranks. He starts with sandpaper to smooth out the inside of the grooves that are forged into the arms.
Then he uses a disc sander to remove the parting lines of the forging dies.
The main polishing comes next. There are many different polishing wheels. Each material has its own wheels. First, a rougher wheel is used (photo at the top of this post), which then is followed by a finer wheel (above).
From start to finish, polishing a crankset takes about an hour. Then the cranks go into an ultrasonic cleaner to remove the residue from the polishing. A final buffing by hand, and they are ready to be assembled as you order them, with any chainring combination from 24 to 52 teeth.
What you end up with is a crank that isn’t just shiny, but also has all the details of the wonderful shape intact. Polishing cranks to this standard is a lot of work, but we believe the final result is worth it. That way, the appearance of our cranks matches their functionality.
The cranks are in stock now. Click here for more information.

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Crank Bolt Wrench

Our René Herse cranks come with classic 15 mm crank bolts. They are beautiful and easy to tighten. However, it can be hard to find a matching 15 mm wrench. Most wrenches have walls that are too thick to fit inside the hole of the crankarm. (We cannot make the hole larger, since we want to use a standard extractor that fits inside the threaded hole.)
When 15 mm crank bolts were the industry standard, many companies offered crank bolt wrenches. The most famous was Campagnolo’s, but TA and others offered similar versions. These wrenches were beautiful and tactile. Aficionados sometimes called them “peanut butter wrenches,” even though I don’t know of anybody who actually has used them to spread peanut butter. Well, you could, and the chrome-plated finish should be dishwasher-safe, too!
Since most companies have gone to Allen heads for their crank bolts, crank bolt wrenches for 15 mm bolts have become hard to find. Many customers instead have used Allen head bolts on their René Herse cranks. Allen bolts work fine, but don’t look as nice.
Now we introduce a new René Herse crank bolt wrench. It’s made from tough CrMo steel, so it will tighten and loosen your crank bolts thousands of times without wearing out. (We’ve tested prototypes for over a year now.) The wrench is polished and chrome-plated, so it looks even nicer than the old-style wrenches from Campagnolo & Co.
In addition to crank bolts, the 15 mm wrench also works for track-style axle nuts. It’s much lighter and a bit smaller than a standard wrench, so fixed gear riders can easily carry it.
The thin wrench has one additional benefit: If you tighten your crank bolts to the point where the wrench starts being uncomfortable, because it digs in your hand, you have reached about 25 Nm, the recommended torque for our cranks. So you don’t need a torque wrench, yet you won’t over- or undertighten your crank bolts.
The crank bolt wrenches are in stock now. Click here for more information.
P.S.: Many of you have asked when we will have the René Herse double and triple cranks back in stock. (Single-speed cranks are in stock.) The new production run has been forged, and most of the machining is complete. The cranks just need to be checked for quality control and polished. We hope to have them in stock in a February, but we cannot predict the inevitable manufacturing delays. Thank you for your patience.

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It's Not Easy to Be Honest

I used to wonder why manufacturers offer things that are popular, even though they don’t work well. I recently read an interview with a BMW engineer, who complained about the huge wheels that the company now puts on their cars. It turns out the large (and heavy) wheels ruin the car’s dynamics, making it drive less well than it would otherwise. “Customers like them, though,” the engineer said. BMW faced a choice of making a better car, or giving customers what they want. They chose the latter.
BMW isn’t the only company that follows trends rather than setting them. Almost everything these days, from soap dispensers to political messages, is focus-grouped, rather than made with conviction. When somebody complains, they hear: “What do you want? Customers asked for it.”
To me, that sounds like a sorry excuse. After all, we pay experts because we don’t know the answers ourselves. How many car buyers are aware of the compromises they incur when specifying larger wheels? (Larger wheels allow you to fit bigger brakes inside, which is why sports cars used to have larger wheels than other cars. However, the increase in unsprung mass compromises comfort and handling.) And how many customers would choose differently if they knew?
I don’t have to think too hard to realize why this is upsetting to me: I want the best! I want a great, responsive ride in a car. I want the same in a bike, and that is why Compass Bicycles doesn’t compromise on our products.
At Compass Bicycles, we do a lot of research that guides our product development. Our research isn’t “market research,” but research into how bicycles and components work. Then we try to communicate our findings to our customers. Unlike most car companies, we sell to enthusiasts who are knowledgeable about what makes a bike perform. This makes our job easier.
I can see the temptation to follow the path of least resistance. Consider our René Herse crank project, where we made a number of decisions that we feel improved the product, but which go against popular opinion:

Crank length: Traditionally, cranks have been offered in multiple, yet very similar lengths, from 165 to 175 mm. (The montage above shows that range. The cranks look similar because they are similar: The longest crank is just 6% longer than the shortest one.)
Large makers use separate forgings for each length, but small makers use one forging with extra material, and then machine the cranks to the desired length. This interrupts the grain structure of the aluminum and weakens the cranks.
For the René Herse cranks, we use a net-shape forging with a perfect grain structure. This means that our cranks are available in one length only, but on the upside, our cranks passed the stringent EN “Racing Bike” standard for fatigue resistance (EN 14781). I know of no other small-production crank that has passed this test.
It may take a little time for cyclists to give up a long-held belief, but in the end, I am confident that our customers prefer a stronger crank, even if it means riding a crank that is 2% shorter or 3% longer than what they usually ride.

Chainring ramps: Chainring ramps only work for matched pairs of rings, and even then it is debatable how much they contribute to better shifting. (Above are two random shifts: One used the ramp, the other did not.)
The René Herse cranks are available with a huge selection of chainrings, so you can get gearing that is perfectly matched to your strength and riding style. This means that we cannot offer matched pairs of rings.
Many aftermarket chainrings aren’t designed as matched pairs, either, and instead feature “cosmetic” ramps that don’t do much. Such a “make-believe” feature is counter to our beliefs. Instead, we optimized the chainring tooth profiles for smoother shifting with any chainring combination. But many customers still wonder why our chainrings don’t have ramps.
Anodized arms: Anodizing still is seen by many as a sign of quality. It protects the finish of aluminum parts, but only until it gets worn off where toestraps or booties touched the arms, to say nothing of scratches. Then the cranks look scruffy, and the aluminum isn’t protected any longer.
The René Herse cranks use a corrosion-resistant alloy that does not need to be protected from the elements. Even after several Colorado winters, customers report that their cranks remain shiny and bright. And if they get scratched, you can re-polish them.

Stainless steel crank bolts: Many people love stainless steel. It’s shiny and does not rust.  What’s not to like? Most people don’t realize that stainless steel is more brittle and not as strong as other steels. We make our crank bolts from strong steel and then have them chrome-plated, so you can can rely on your crank bolts.
We stand behind these choices, which make our cranks stronger, better-looking and more versatile than they would be otherwise. Even so, I know we sell fewer cranks than we would otherwise: Some customers will be turned away because the cranks aren’t available in “their” length, or they want ramped chainrings, anodized arms, and/or stainless steel bolts.
Why didn’t we take the path of least resistance and offer what customers want? We’d save money during production, we’d save time explaining, and we’d sell more cranks.
The reason is simple: We ride these cranks on our own bikes, and we wouldn’t want them compromised in any way. We want the best, and fortunately, we have the freedom to make our components the way we want them.

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Trouble with STI Triples

Triple cranks are a good choice for some riders. The most common shifting system for triple cranks, Shimano’s STI, only works with Shimano chainrings. Unfortunately, Shimano’s chainring combinations are of limited use to most riders. If you want to customize your chainring sizes, you will have to use downtube or bar-end shifters, plus a front derailleur with a smooth inner cage, to make more useful triple cranks work.
On current-production road bikes, triples have almost become obsolete, because 11-speed cassettes provide such a large gear range that a third chainring no longer is needed. SRAM doesn’t even make “road” triples, but Shimano still offers them, and Campagnolo did so until recently.
Even with 10-speed cassettes, triples remain a good choice for loaded bikes and/or slower riders. These bikes and riders need a relatively small “base gear,” yet they still pedal at high speeds on slight downhills and with strong tailwinds, so they need reasonably large gears, too.
For these riders, it makes sense to have a large “top speed” chainring, a middle “cruising” chainring, and a small “climbing” chainring for steeper hills. (Stronger riders can combine the “top speed” and “cruising” chainrings into a single chainring and use a compact double.)
For triples to work well, you want to select your chainrings based on your riding style. However, Shimano offers only a single combination: 50-39-30. This is an odd combination: A rider who finds the relatively small 39-tooth “cruising” chainring useful will probably need a “climbing” chainring with fewer than 30 teeth.
More useful triple chainring combinations would be 46-40-26 or 44-38-24, with large rings small enough to be useful for normal riders, with middle rings sized for general riding, and small rings that allow climbing steep hills at low speeds.
One of the appeals of our René Herse cranks is the custom gearing. You can choose any ring combination from 24 to 50 teeth. The René Herse crank is designed to drop right into the clearances of a modern crank, so you can replace your existing crank with one that has more appropriate gearing. The René Herse cranks work great for most riders, with one exception: riders who use Shimano STI with a triple. It took us a while to figure out why STI triples are so troublesome.
After doing a lot of testing, we found that there are two separate problems. One concerns front derailleurs, the other is related to the way STI executes front shifts.
Many front derailleurs for triples have a channel pressed into the inner cage. This is designed to lift the chain onto the big chainring when you upshift. It works only if the channel matches the position of the chain on the middle ring. A derailleur like this works only with a very narrow range of chainring combinations.
If you use a differently-sized middle ring, the channel no longer lines up with the chain as you start the shift. In the photo above, the channel is above the chain. The chain gets stuck below the channel, and it’s almost impossible to shift to the large ring.
The solution to this problem is simple: Use a front derailleur for doubles, which has a smooth cage and no channels (above).
Won’t the lack of channels and other “shift aids” make it shift poorly? Front shifts are not  demanding: The derailleur only needs to push the chain into the rotating teeth of the larger chainring, which picks up the chain and executes the shift. A front derailleur does not need a complex shape to work well.
A good option is the Shimano CX-70 front derailleur (above). This derailleur is designed for cyclocross bikes with smaller chainrings, so its curve matches that of the smaller rings, and its cage is short enough that it doesn’t hit the chainstays, which can happen when you use standard derailleurs with small chainrings. The CX-70 derailleur is a great choice, whether you run a double or a triple.
Using a front derailleur with a smooth cage addresses one problem, but another problem remains: During shifts from the small to the middle ring, to prevent the chain from overshifting straight onto the big ring, triple levers for STI/Ergopower move the chain only part-way, just far enough for a pin on the middle ring to pick up the chain.
This is very different from how shifters for two chainrings work: The derailleur pushes the chain sideways until it catches on any tooth of the larger chainring. The chain then is lifted up and threads itself onto the larger chainring, no matter how the teeth are aligned.
Now you see why STI and Ergopower triples won’t work with our cranks: Without properly designed ramps and pins, the derailleur won’t move the chain far enough to be picked up by the next chainring! Many aftermarket chainrings with “cosmetic” pins and ramps that are not aligned in the optimal chain path also will not work well with STI. (Sometimes, careful setup can make it sort of work, but the shifting won’t be as reliable.)
Why don’t we make triple-crank chainrings with ramps and pins? To offer truly outstanding shifting performance, ramped-and-pinned chainrings must be designed in matched sets. The appeal of the Rene Herse cranks is that you can mix and match chainrings as you like, but that means that there simply are too many possible chainring combinations. We’d have to make hundreds of different chainrings!

  • If you want to use STI/Ergopower and triple cranks, you have to stick with Shimano’s stock cranks and chainrings, whether the gear ratios work for you or not.
  • If you want to use a triple with custom gearing, use downtube or bar-end shifters. Make sure you use a smooth-cage front derailleur no matter which shifting system you use.
  • If you don’t want to give up STI/Ergopower, maybe an ultra-compact double will work better for you. A 44-28 may give you more useful gears than Shimano’s triple chainring combinations.

What about STI for double cranks?
Shimano’s STI for double chainrings shifts fine with chainrings that don’t have pins and ramps, but for optimum shifting performance, we now offer the Rene Herse 9/10/11-speed cranks with ramped-and-pinned chainrings.
Addition (3/7/2015): A reader pointed out that the “top pull” version of the CX-70 derailleur does not swing far enough to shift a triple crank. Only the standard “bottom pull” version works for triples.
Further reading:
– Blog post on How to select your chainrings.
How Ramped Chainrings Work. Bicycle Quarterly Vol. 11, No. 2.
– More information about Rene Herse cranks.

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Passing the Test

When we designed the new René Herse cranks, our goal was to create a crank that was as reliable and safe as any on the market. After all, we ride these cranks ourselves. We are especially proud that these cranks pass the stringent EN standards for racing bikes (EN 14781) with respect to fatigue resistance. We had our cranks tested by the Taiwanese subsidiary of the prestigious Swiss SGS testing lab. (Some other labs are reputed to be “easier,” but we wanted honest results, not a rubber stamping of our product.)
During the design process, we researched how other crank makers tested their cranks. We found that of the “boutique” and “classic” cranks on the market, none had passed the “Racing Bike” standard for fatigue resistance.
A number of makers (TA, Electra) had tested their cranks to the “City and Trekking Bike” standard. One company had done “some internal testing,” but didn’t recall the protocol. A budget maker of cyclotouring components did not provide any information. We later learned from an internal source that they had not tested their cranks at all.
The “Racing Bike” standard is especially demanding because it loads the cranks with 1800 N during 100,000 cycles (above). By comparison, the “City and Trekking Bike” standard uses a load of only 1300 N.
I am lucky to know people in the bike industry from my days as a translator for several high-end bike companies. These engineers were very helpful when we designed our cranks, but they all doubted that a slender, classic crank could pass the “Racing Bike” standard. This demanding test is one of the reasons why cranks have become so bulky in recent years.
How does the René Herse crank manage to pass a test that other cranks fail, without adding the bulk that you see on many modern cranks? It’s a combination of factors:
Proven design. The René Herse cranks have been around for more than 70 years (above during the mid-1950s), so we knew we had a sound design before we even did the first test.
The best materials and suppliers. We did not look for the least expensive forging company, but for the best one. We also selected the alloy of the arms for strength and corrosion resistance.
Net-shape forging. The raw forging already has the final shape of the crank, so the grain structure of the aluminum is not interrupted by machining. As a down side, this means that we can offer only a single crank length. We feel that the improved strength is more important than enabling customers to choose cranks that are 2% shorter or 2% longer than the 171 mm we offer.
A few other, proprietary manufacturing techniques maximize the strength of our cranks. None of these are rocket-science, but we were surprised that they are not commonly used during the production of bicycle cranks.
Of course, other cranks have been used without a rash of failures. Perhaps we are overly cautious, but I sleep better at night knowing that our cranks meet the most stringent standards. Crank breakages are rare, but they can have very unpleasant consequences.
Our cranks should last as long and be as safe as the best racing cranks you can buy, no matter how hard you ride. Because for all their beauty, René Herse’s bikes were intended to be ridden hard, as shown by Lucien Détée and Gilbert Bulté. In the photo below, they are on the way to setting a new tandem record at the Journée Vélocio hillclimb. For more information on our cranks, click here.

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Will I be able to get chainrings?

Question from a potential customer: “If I purchase a Rene Herse crankset with its non-standard bolt-circle diameter, what guarantee do I have that Compass Bicycles will continue production of the chainrings for 5, 10 or 15 years?”
Compass Bicycles makes products that we expect to last for decades. We have taken every care in the design and manufacture to ensure that you can enjoy them for a long time. In this context, being able to get replacement parts is important.
Will you be able to get chainrings when your first set wears out?
The good news is that you won’t need new chainrings for a long time. Our chainrings are precision-machined from 7075 aluminum, which is very hard and long-wearing. Expect to get about 5-8 times as many miles out of these rings than you get out of less expensive rings that are made from 6000-series aluminum. (I used to get about 50,000 km / 30,000 miles out of a set of Campagnolo chainrings of similar quality.)
It may take a while, but eventually your chainrings will wear out. Anybody who has tried to replace or repair a 9-speed brake-shift lever just a decade after it was “state-of-the-art” knows how quickly big manufacturers declare a product obsolete. In fact, Campagnolo apparently is about to end their support for 10-speed components.
Compass Bicycles is different, because we are committed to our designs. We won’t change them for the sake of offering something “new.” René Herse cranks have been around since 1938. (The photo shows a tandem from 1947.) It’s hard to see how they could be improved. For you, this means that future chainrings will fit onto the cranks you buy today.
In fact, today’s René Herse chainrings fit on all Herse cranks made after 1960, and earlier cranks can be adapted to fit the current chainrings. So even riders who bought their René Herses more than 70 years ago can get chainrings for their bikes again! As long as Compass Bicycles is around, you should be able to get chainrings.
What if Compass Bicycles goes out of business? We promise that we will do our utmost to avoid this eventuality!

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100% Quality Control

Some customers of our René Herse cranks have noticed that their brand-new cranks show traces of having been mounted on a bottom bracket. Did they receive used cranks by accident? No, the cranks are brand-new.
As part of our quality control, we mount each crank, with the chainrings the customer ordered, on a bottom bracket. We want to make sure that the chainrings don’t wobble. Our tolerances for chainring “runout” are tighter than most in the industry, but when you have a flexible frame, the frame flex and runout of the chainrings can add up. Having your chain rub on the front derailleur can be annoying.

In making the new René Herse cranks, we found out why this design has not been copied more widely. It offers many advantages over other cranks, but it is much harder to make. Conventional cranks have a large bolt-circle diameter and four or five beefy arms, so you can pull even a slightly out-of-round chainring into shape. With three lightweight arms and a small bolt-circle diameter, very small irregularities are translated into a noticeable wobble on the outside edge of the chainring. Thus, the manufacturing tolerances have to be much more precise. To make sure that every crank meets our standards, we check it after it is assembled. Then we send the new cranks to the customer.
100% quality control used to be common among high-end makers. In the days when Campagnolo still gave a lifetime warranty on their products, they also mounted every crank before it left the factory. Mike Kone, who used to own Bicycle Classics and who has handled more “New Old Stock” Campagnolo parts than almost anybody, noticed mounting traces on every “NOS” Campagnolo Nuovo and Super Record crank.
Today, many companies leave the quality control to their customers. If something is not up to standards, the customer can return it for a free replacement. That is a lot cheaper than actually checking your products. And since not every customer will send back a sub-standard product, you have fewer rejects.
When we design our products and check their quality, I often ask myself the question: “What would René Herse have done?” Herse was known as a perfectionist. He did not send out a product without being sure that it performed as intended. It is our goal to live up to his standards.

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How to Choose Your Chainrings

When we received another shipment of Rene Herse cranks recently, we built up and filled our pre-orders first. Some are shown above. All the cranks shown have different setups, except two. (Can you spot the two identical ones?)

There are a dozen different chainring combinations in the photo above, yet they represent only a small fraction of the possible chainring choices with our new cranks. We currently offer more than 100 different useful crank configurations to customize the crank to your power output and pedal style.

Compare that to most makers: Not counting track cranks, Shimano offers seven chainring combinations for their Dura-Ace cranks. Ultegra is available in four combinations, including a single triple. Campagnolo offers just three combinations for their Record cranks. None of the big makers offer 48-32, 44-28 or 46-36-24, combinations that are very useful for many riders.

Our Rene Herse cranks can be set up in even more chainring combinations, but our 100 combinations count only those that make sense and offer excellent shifting performance. Here is how to figure out an ideal chainring choice for you. (This post is excerpted from a more detailed article on gearing in the Summer 2012 issue of Bicycle Quarterly.)

One big rule is that the difference between adjacent chainrings ideally should not be larger than 16 teeth. You can use a larger difference – I once tested a bike with a 52-26 double – but your shifting will not be ideal. For example, a 48-32 (16 tooth difference) will shift fine with most front derailleurs, but a 48-30 (18 tooth difference) may require trimming of the front derailleur after each front shift. A large chainring difference also can result in the chain rubbing on the large chainring when you ride in the small chainring in the front and on one of the smaller cogs in the rear.

With this in mind, you can freely spec your favorite chainring combination. When I select my gearing, I think of three gears:

  • Base gear: This is the gear I mostly use on flat roads when spinning along.
  • High gear: This is the largest gear that I use when I am sprinting for a city limit sign with friends, or riding with a powerful tailwind.
  • Low gear: This is the smallest gear I need on the roads I usually ride.

In addition to covering the range from low to high gear, a good gear selection will do the following:

  • Put the base gear in the middle of the rear freewheel/cassette, so that I can adjust to changes in speed and terrain with a simple shift or two in the rear.
  • Provide small enough steps between gears, so that I can continue pedaling seamlessly.

I don’t worry about duplicate gears, if they fall in the range where I ride frequently. In fact, some overlap is not just OK, it’s desirable.

The worst gearing I have ever ridden was that bike I mentioned above with the 52-26 chainrings. It had a 14-28 freewheel. On paper, this might look ideal: a huge gear range, and only one duplicate gear. On the road, it was far from perfect: In the big ring, the gearing was just a tad too large for slight uphills, while in the small ring, the gears were too small for the flats. As a result, I was shifting all the time, not only the front, but also almost all the way across the rear. This really broke my rhythm.

If I were riding that bike all the time, I’d simply add a third chainring (which is relatively easy with René Herse cranks).* Adding a 44-tooth ring would not have changed the gear range, and added five duplicate gears. On paper, that would be useless, but on the road, those would be the gears I would use 90% of the time! With the 44-tooth chainring, my base gear would be in the middle of the freewheel, and if the road tilts up or down a bit, I’d just need a simple shift on the rear to be in the right gear again. The 50-tooth chainring might be useful for super-fast rides, while the 26-tooth ring would get me up any hill.

Double or Triple?
The decision comes down to the gear range you need and which gears you ride most of the time. If your ‘base gear’ is close to your ‘high gear,’ then you can accommodate both on the same chainring. That means that you can use a double.

If your base gear is right in the middle between your ‘high’ and ‘low’ gears, then a double may put you between the two rings most of the time. Get a triple instead!

Alternatively, if you don’t like the wider tread (Q factor) of a triple, think about reducing your high gear. You don’t give up much – pedaling on steep downhills is slower than tucking in the aero tuck anyhow – and you may be able to use a double.

Choosing your gearing well will increase the enjoyment of your ride. Click here to see the chainring choices that are available for the Rene Herse cranks. For a more detail and examples of chainring choices, check out the Summer 2012 issue of Bicycle Quarterly.

* To convert a double René Herse crank to a triple, you need an extra chainring, longer chainring bolts, and (usually) a longer bottom bracket spindle.

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René Herse Cranks in Stock

We just received a new shipment of René Herse cranks. In addition to the double and triple cranks, this production run includes the single-speed cranks (shown above). We also have all chainring sizes in stock (except 50 teeth, which are due to arrive in Seattle in a few days).

The single-speed cranks are machined differently on the back (above): There is no shelf for the second chainring, and the chainring nuts are recessed into the spider. Not only does this look nice, but it allows you to run an ultra-narrow tread (Q factor).

We now also have the new René Herse tandem cranks in stock. The left-side chainrings always are 30 teeth. Since these rings don’t need to shift, we gave them a special tooth profile for extra-long wear. For the right-side crank, you have the same choice of single/double/triple chainrings in all sizes between 24 and 50 teeth.

We now offer the chainring bolts and spacers separately, so you can convert your cranks from double to triple or vice versa.
We appreciate your patience while we worked on the second production run. It takes time and dedicated work to maintain our high quality standards, and our engineer in Taiwan has been working overtime to make this happen. We think the end product is worth the wait. More information on the René Herse cranks is here.

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René Herse Cranks Sold Out

The first production run of the new René Herse cranks has sold out. Reports from users have been very positive. The cranks work well with current 10-speed drivetrains, as well as classic setups with 5-9 cogs in the rear.
The second production run is under way. In a month or two, new cranks and chainrings should arrive here. In the mean time, you can pre-order your cranks. Or watch this blog: We’ll announce when the new shipment arrives.

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To grease or not to grease?

Should one grease the tapers of bottom bracket spindles before installing the cranks? Few topics spur as much controversy among bike mechanics as this question.
In the old days, Campagnolo not only recommended mounting the cranks dry, they even suggested degreasing the tapers. The concern was that grease might facilitate the crank slide up further and further on the tapers. And since many of us learned about bicycles when Campagnolo was the undisputed king of components, the word from Vicenza was treated as gospel.
More recently, I worked for Race Face as a technical writer and translator, and  their engineers disagreed. They advised: “Grease the tapers, but make sure you only tighten the bolts once, then leave them alone.” Their tests had shown that a “dry” spindle/crank interface did not result in a consistent press-fit between the parts.
As we developed the new René Herse cranks, we discussed this topic without coming to a conclusion. In the mean time, our engineer mounted the first test cranks without grease, and found that they had unacceptable levels of runout of the chainrings – the chainrings didn’t run as true as we would have liked. (“Unacceptable” means that the runout was visible even if it did not affect the function or performance.) When the runout changed each time he mounted the cranks, we realized that the cranks were not seating uniformly on the taper.
What exactly was happening? Imagine the crank and spindle surfaces as tectonic plates that slide past each other as the crank bolts are tightened. If you grease the interface, they will slide smoothly until you stop turning the bolt when it is tight. If the interface is “dry,” the crank catches on the spindle. This builds up tension, which then is released in an “earthquake.” Even with the same torque, the crank will sit differently, depending on whether the tension has been released or not, before you stop turning the bolt. With grease, the crank’s position was more uniform, as the crank slid smoothly onto the spindle.
What about the crank arms “migrating” further and further onto the spindle each time you mount the cranks? To test this, we mounted a René Herse crank, tightened it to 25 Nm, then took it off, mounted it with 30 Nm … we repeated this 5 times, increasing the torque by 5 Nm each time until we reached 50 Nm. The goal was to find out when the crank would be destroyed. To our surprise, the crank did not move any further onto the spindle. We could not destroy the cranks in this way. A 1990s Campagnolo C-Record crank that we tested for comparison slid further and further onto the crank. We stopped the experiment early to avoid breaking the classic Campagnolo crank.
The difference between the two cranks appears to be that the new René Herse cranks have a forged taper. This makes that part of the crank assembly much stronger. The C-Record crank appears to have a machined taper. Every time the crank gets mounted on the spindle, the aluminum moves – in fact, mounting the crank acts in the same way as a forging process. It is likely that this process would stop eventually, but I’d rather not experiment with a classic crank.
So for our René Herse cranks, we recommend that you lightly grease the crank spindle. Also grease the treads of the bolts, but not the underside of the bolt head. (The underside of the bolt head should interlock with the crank, so it doesn’t come loose.) Then tighten the bolts. Check after your first ride that the bolts are tight. Thereafter, leave them alone.
Crank bolts can loosen over time, but that does not mean that you should re-tighten them. Instead, remove your cranks every couple of years and inspect them for cracks. (You should do this with all cranks, no matter the brand.) Then put them back on, and enjoy them some more. Treated like this, quality cranks will last most riders for many decades.

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René Herse Cranks are Here!

Customers who pre-ordered their René Herse cranks before February 1 should receive a box in the next few days. Inside…

…is the new René Herse crank. It is delivered with our custom crank bolts and pedal washers. We are ramping up production slowly to ensure the cranks are made to our quality standards. Even though we work with the best suppliers, there have been challenges. The first batch arrived last week. It’s already sold out, thanks to our pre-orders. More cranks are expected to arrive later this week. Then we will be able to fill all pre-orders (except for single-ring and tandem cranks, which are machined separately), as well as have more in stock. This week’s delivery should include all chainring sizes ranging from 24 to 50 teeth.

We are proud of our custom-made René Herse crank bolts. Like the classic Herse crank bolts, they incorporate the washers, so you never risk forgetting to remove the washer and stripping your crank threads as your crank puller pushes on the washer instead of the bottom bracket spindle. The bolts are made from high-strength steel (Grade 8.8) and chrome-plated. (Stainless steel is not strong enough for the forces required to properly seat a crank on a square taper.)
In addition to including the crank bolts with our cranks, we also sell them separately. I plan to install them on most of my bikes, to improve their appearance and function. (Like René Herse, I don’t use dust shields on my cranks. With these bolts, there is no reason to hide them.)
The bolts fit on (almost) any traditional crank/bottom bracket combination. The head fits a 15 mm crank wrench, like old-style Campagnolo (and many other) crank bolts.

Our cranks also come with pedal washers. These small parts can make a real difference when the time comes to remove your pedals. They provide a smoother transition from the pedal spindle to the crank, which can prevent the spindle edge from digging into the crank. We also offer these separately.
For more information, see Compass Bicycles web site.

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Pre-Orders for René Herse Cranks

Developing an excellent product takes time and care. The first run of our new René Herse cranks has been forged. Above, you see a raw forging being removed from the forging die.

Above are the raw forgings for the crankarms of the first production run (three containers in the foreground). Around the same time, the forge was making suspension linkages for 2013 model year mountain bikes (talk about a long lead-time!).

Now our chainring tabs, square tapers and pedal eyes have to be machined (above). The first batch of 50 cranksets is being machined right now, from which we will check all the tolerances to make sure the tapers are accurate and the chainrings have the absolute minimum runout possible. Once we have ensured that everything meets our high standards, the full production run will be machined.

Our engineer in Taiwan (above on the left) visits the forging and CNC shops every week to make sure everything is to spec.
The first 50 sets of cranks should arrive here in late December or early January, together with the 48-tooth and 32-tooth chainrings. Other chainring sizes, more cranks (including single-chainring and tandem models) will follow shortly thereafter.

We are now taking pre-orders for the René Herse cranks, which will be filled “first come, first served.” Obviously, if you order a 48-32 double, you’ll get yours from the very first shipment, whereas other sizes will take a little longer (but not much). Tandem cranks and triples for half-step gearing probably will come last. Click here for more information.
At this time, we also would like to announce that Compass Bicycles is the sole manufacturer of René Herse cranks.  Herse Bicycles Inc. of Boulder, CO, has decided to focus on their core competencies of making superb custom-made bicycles under the René Herse brand. The René Herse cranks will be available directly from Compass Bicycles. The cranks also will be available from bicycle retailers.

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Net-Shape Forging and Crank Length

Net-Shape Forging
The new René Herse cranks will be offered in one length only, 171 mm, which allows us to have the cranks forged to their final shape. (The photo above shows the raw forging.) The process is called “net-shape forging.” The grain structure of the aluminum is aligned during the forging process, so that it follows the contours of the crank. Net-shape forging optimizes the crank’s strength and enables us to offer a lightweight part without undue concerns about reliability.
Machining Cranks to Length
When small-production cranks are offered in different lengths, they usually are made with an adaptable forging, like the raw forging for the TA “Pro 5 vis” cranks shown below.

On the right side, you see how the pedal eye area is elongated. The crank is machined to the correct length by cutting away material near the pedal eye. The following illustrates what happens when you do extensive machining on a forging.

Above is a schematic drawing of a raw forging. You can see how the grain structure conforms to the final shape. This makes for a very strong part.

When we cut off one end, we interrupt the grain structure at that end. Each of these interruptions is a weak spot. On a crank, the interruptions occur at the pedal eye – one of the places that are subject to the most stress. If a crank breaks, it often happens at the pedal eye. Machining the crank to length has eliminated the advantages of the forging process in this area.
“Net-shape” forging keeps the grain of the crank intact. The result is a stronger crank. If you want to offer multiple lengths, a better way is to make separate forging dies for each length. However, this multiplies the cost, especially with small production runs, whereas machining the cranks to length costs very little, because the cranks already are going to be machined for the pedal eye, chainring interfaces and spindle taper anyhow.
The Importance of Crank Length
But what about riders who need a different crank length? I used to think that I was highly sensitive to crank length. I found the 175 mm-long Shimano Deore triple cranks on my touring bike much harder to spin than the 172.5 mm Campagnolo cranks on my racing bike. It was obvious to me that the 2.5 mm extra length made the touring bike’s cranks difficult to spin.
Then I visited my friends Pamela and John in Boston. I had brought my Bike Friday along, but since we were to enter a 300 km brevet together, Pamela suggested that I should ride a bike with better performance. They were to ride their tandem, and John’s bike fit me fine, so why not take it instead? Very well, except it was equipped with 175 mm cranks, and I was concerned about being able to spin such long cranks. John scrounged around and tried to find shorter cranks for me, but his bike was optimized for narrow tread (Q factor), and none of the shorter cranks would fit. I decided to take a chance and ride John’s bike with the long cranks.
To my surprised, I could spin his 175 mm cranks very well. I had a great ride on the hilly roads of Connecticut with my friends, and never felt bogged down like I did on my touring bike. I realized that it had not been the length of the Deore cranks that inhibited my spin, but their width. Their tread (Q factor) was at least 20 mm wider than my Campagnolo cranks. John’s cranks were as long as the Deore cranks, but their tread (Q factor) was almost as narrow as that of my Campagnolo cranks.

Let’s look at the length by itself: The difference of 2.5 mm amounts to only 1.4% of the total crank length. The cranks in the photoshopped image show the range that most manufacturers offer, from 165 mm on the left up to 175 mm on the right. The cranks look similar because they are similar: The longest crank is just 6% longer than the shortest one.
Imagine putting five random people next to each other: Their leg lengths would not be within 6% like the lengths of the cranks in the image. If we wanted to scale our cranks to our leg length, we would need lengths between 140 and 210 mm, as Lennard Zinn suggests. And according to this formula, I would need 186 mm cranks.
TA at least offers their cranks in lengths between 150 and 185 mm, but most cranks are available only in a very narrow range between 165 and 175 mm. People’s inseams and thigh lengths vary by at least 30%, yet most cranks vary in length by less than 10%. There are two possible explanations:

  1. Crank length does not matter for most riders, and the small differences in the commonly available crank lengths don’t affect how the cranks feel and perform.
  2. Crank length matters, and the crank makers have it all wrong. They should offer lengths that vary by 30% or more.

My experience suggests that 1. is correct, that small differences in crank length do not make a big difference. Today, I am as happy spinning the 175 mm cranks on Mark’s bike as I am on an old René Herse with 165 mm cranks. Compared to other factors, such as the tread (Q factor) and the flex characteristics of the frame (my touring bike with the Deore cranks also had a stiffer frame that contributed to the “bogged-down” feeling), crank length appears to matter little for most riders.
If you are outside the “normal” size range of cyclists, then you may benefit from significantly longer or shorter cranks. By significant, I mean not just a 165 mm or a 175 mm crank instead of a 170 mm. For example, I went to some lengths to put 150 mm cranks on my children’s bikes, and very tall riders may benefit from significantly longer cranks.

We are confident that our 171 mm cranks will work well for the vast majority of cyclists. For those who “need” a 175 mm or a 165 mm crank, we ask them to re-consider whether the 2-3% shorter or longer René Herse cranks really will feel very different. If future research finds that crank length does matter after all, then all makers will have to start making 140 mm and 210 mm cranks. In that case, we will make additional forging dies for those lengths. Until then, we hope that most riders will be happy with our 171 mm cranks, even if they are 4 mm shorter or 6 mm longer than their preferred length. In our opinion, the advantage of a stronger crank is worth the slight compromise in the length.

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René Herse Cranks: Prices and Availability

The new René Herse cranks have entered production. The arms are being forged, the chainrings are being machined, and the crank bolts are being made, each by specialist manufacturers who are among the best in their trade. The photo above shows the final production version of the arms and chainrings. (The crank bolt still is a prototype.)
We plan to have the cranks in stock for the Holidays. We also have finalized the prices: $385 for single- and double-chainring cranksets, and $440 for a triple. We will offer tandem cranksets as well.
The double-chainring cranks are designed for a 113 mm JIS bottom bracket, resulting in a tread (Q factor) of 142 mm with a standard chainline. (If you ride mostly on the big ring, you can use a shorter BB spindle to move the cranks inward a bit, if your frame permits. This will reduce the tread/Q factor by up to 6 mm.)
The new René Herse cranks are compatible with many bottom brackets, including the excellent SKF bottom bracket available from Compass Bicycles.
I am looking forward to putting these cranks on my new randonneur bike!

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History of Aluminum Cranks

During the development of our new René Herse cranks over the last two years, I have been thinking a lot about crank design. Modern cranks are an interesting story of standards that evolved until nobody remembers why they were adopted in the first place. Here are a few questions that I tried to answer:

  • Why do triple cranks have two different bolt-circle diameters?
  • Why do makers offer “compact” and regular cranks, when you could make 53-tooth chainrings for “compact” cranks and offer only a single, more versatile model?
  • Why do “road” cranks have five-arm spiders, but many “mountain bike” cranks have only four, and some only three?

When something doesn’t appear to make sense, it often helps to look at how it evolved over time.
The first successful aluminum cranks were introduced in 1933 by Stronglight (photo at the top). They used a square taper fitting on the spindle instead of the cotters used by most steel cranks at the time. As their name implied, these cranks were strong and light.
They had one drawback. The chainring attached to a small flange on the right crankarm, as was common among cranks at the time. If you ran two or more chainrings, the additional chainrings attached to the big ring with bolts, nuts and spacers. Installing the chainrings on these cranks is a fiddly business. The small bolts are under-dimensioned. It is hard to tighten them enough without breaking them.

The next modern aluminum crank was offered by René Herse in 1938 (above; 1950s tandem version shown). Herse mounted his chainrings to a larger spider instead of a flange. Using three arms and a bolt-circle diameter of 70 mm, these cranks preserved all the advantages of the Stronglight, while making it much easier to attach the chainrings. The cranks could be set up as a single, double or triple with any chainring combination down to 24 teeth.
When Herse began to offer complete bicycles in 1940, his cranks were available only on his bikes.  If you wanted a René Herse crank, you had to buy a René Herse bike. This precluded a more widespread adoption of this great design.

Starting in the late 1940s, Tullio Campagnolo adopted a number of cyclotouring components for racing. The first was the Gran Sport derailleur, which was based on the Nivex parallelogram derailleur. (Campagnolo famously bought two Nivex derailleurs from Alex Singer the year before he introduced the Gran Sport. You can read Bicycle Quarterly’s article on the development of the Gran Sport here.) The Gran Sport was so successful that it set the mold for all modern derailleurs. Even Shimano’s electronic Di2 rear derailleur can trace its ancestry directly to the Gran Sport.
When Campagnolo offered his first cranks in 1958 (above, 1965 version shown), Campagnolo used five arms for the spider instead of Herse’s three arms. Perhaps he thought that racers needed more support for the chainrings? Like Herse, he considered the smallest chainring his customers would use.  At the time, most racers used a small chainring with 47 teeth. The result was a 151 mm bolt-circle diameter.

Around the same time, triple cranks were becoming popular among racers. Campagnolo offered a “Strada” model that simply used longer chainring bolts and nuts, plus spacers, so you could bolt a third chainring to your cranks. Of course, a triple with a small ring of 47 teeth was of little use to most riders.
Some mechanics instead retrofitted Campagnolo cranks with a third ring, with a smaller bolt circle (from Stronglight or TA). They drilled holes into the crank’s spider, tapped them, and attached the third ring with spacers. The photo above shows one of these home-made conversions. Since it’s a tandem, you see a fourth chainring, which is on the other side of the bike.
In the 1970s, Campagnolo began offering a factory-made version of this design. The Campagnolo triple appears to have been the first production crank with two different bolt-circle diameters.
For decades, most component makers copied Campagnolo, sometimes with small modifications. Shimano’s cranks used a 130 mm bolt-circle diameter that allowed using chainrings down to 38 teeth. Campagnolo reduced their bolt-circle diameter first to 144 mm (42-tooth chainrings), then to 135 mm (39-tooth chainrings).

When mountain bikes popularized triple chainrings, the crank makers copied the dual bolt-circle diameter of the old Campagnolo “retrofit” triple cranks (above; the second set of bolts is hidden on the other side of the crank). Component makers reduced the bolt-circle diameters to allow the use of smaller chainrings, but did not reexamine whether it made sense to have two different bolt circles on the same cranks.

During the 1980s, Campagnolo tried to break away from the dual-bolt circle diameter “retrofit” cranks. Their Gran Sport Touring, Victory and Triomphe cranks had a smaller 116 mm bolt-circle diameter (above), so they could be equipped as doubles or triples, with chainrings down to 36 teeth. (It appears that Campagnolo could not envision anybody using rings smaller than 36 teeth.)
The basic idea was sound, but it fell by the wayside as Shimano began to dominate the component market. When Campagnolo offered a road triple again in the 1990s, they were back to two different bolt circles.

In recent years, Shimano’s mountain bike cranks have moved away from the five-arm spider. To save weight, they now use four arms. However, the two bolt circles remain.

On triple cranks for the road, Shimano remains faithful to the tradition of five-arm spiders and multiple bolt circles, even though the extra arms and larger bolt circle for the outer rings provide no advantage.

In recent years, many riders found they needed chainrings smaller than the 39- or 38-teeth offered by racing cranks. Crank makers could have reduced the bolt-circle diameter further, just like Campagnolo had in the past. Instead, they offered additional “compact” models (above) with a 110 mm bolt circle. This bolt circle limits the smallest ring to 34 teeth, even though many riders could use smaller chainrings. The crank makers continue to offer the larger bolt circles for their “standard” cranks.

Even today, the old René Herse design remains the most logical: It allows using any chainring combination. It’s lighter than most modern cranks, because it uses only as much material as needed. The Herse cranks did not serve as a template for the industry because they were too rare and mostly unknown when “modern” cranks were introduced during the 1980s, 1990s and 2000s. Instead, everybody copied the Campagnolo cranks, which initially were intended for ultra-strong racers, and then retrofitted with a third chainring for those not strong enough to climb hills in a 47-tooth (and later 42-tooth) chainring. It appears that nobody took a clean sheet of paper and tried to come up with a more rational design for a bicycle crank.
We are proud to reintroduce René Herse cranks, so that today’s cyclists can enjoy the benefits of light weight, narrow tread (Q factor), unlimited chainring choices, and easy setup.

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René Herse Crank Weight

In our original announcement of the new René Herse cranks, we wrote that they were lighter than Campagnolo Record Carbon cranks. A few readers asked us to substantiate this. We weighed the cranks on Bicycle Quarterly’s precision scale (above).
We don’t have the final chainrings for our new cranks yet, so the weight may still change by a few grams, but here is the comparison:
René Herse (171 mm):
Right crank (48-32 chainrings, steel bolts): 385 g
Left crank: 163 g
Set: 548 g
Campagnolo Record Carbon (2006 model, square taper, 175 mm):
Right crank (53-39 chainrings, aluminum bolts): 444 g
Left crank: 225 g
Set: 669 g
The two cranks are not directly comparable, since the Campagnolo crank is slightly longer and has somewhat larger chainrings. However, comparing the left crankarms (which don’t have chainrings), you see that the Campagnolo arms are 62 grams (38%) heavier than the René Herse crankarms. The right arms are 59 grams heavier, indicating that chainrings and bolts weigh about the same on both cranks. (Campagnolo’s larger chainrings are thinner, and they use aluminum bolts, which makes up for their slightly larger size and greater number of bolts.)
We weighed the 2006 model, because it was the last time Campagnolo offered a separate crank without an integrated bottom bracket. Current Campagnolo cranks have integrated bottom bracket spindles. The spindles have thin walls and use very small bearings, which saves significant weight. If we include a 1950s-style René Herse bottom bracket with extra-large bearings that are pressed straight into the bottom bracket shell, the comparison is as follows:
René Herse:
Cranks: 548 g
Bottom bracket (110 mm, with bearings and dust caps): 235 g
Crank bolts (2): 31 g
Total: 814 g
Campagnolo (2011 Record Ultra-Torque, 50-34 rings):
Cranks with BB spindle: 622 g*
BB cups: 54 g*
Total: 679 g*
*Campagnolo’s claimed weight.

Clearly, the low weight of modern cranks is mostly due to the superlight bottom brackets, rather than the cranks themselves. With the bottom bracket, the latest Campagnolo carbon cranks weigh 135 grams less than an equivalent set of René Herse components. Much of the Herse’s extra weight is in the large bearings (72 g for two bearings). On the plus side, the bearings last for decades without overhaul. For me, that is worth a few extra grams.

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René Herse Cranks – Strong Enough?

When we presented the new René Herse cranks last week, a number of people wondered whether they would be strong enough. After all, most cranks have four or five spider arms, whereas the Herse cranks use only three. And what about the small bolt-circle diameter? Does it support the chainrings sufficiently?
Classic components have one major advantage: They have proven themselves. We don’t have to guess whether they are a good design, we can look at their record. Or records – because numerous performance records have been set with René Herse cranks.
The photo above is from the Summer 2011 Bicycle Quarterly. It shows Lucien Détée and Gilbert Bulté on their way to a record in the Journée Vélocio hillclimb. That climb was about 3 km (2 miles) long, up a steep hill near Paris that maxed out at 15%.
Their Herse tandem is equipped with Herse cranks. Think of the forces on that large 54-tooth chainring as this powerful team sprints out of the saddle, up this steep hill, in an all-out effort.
Détée and Bulté were among the strongest randonneurs of their era. They just had been the fastest riders in the 1956 Paris-Brest-Paris. They also set a record in the 100 km (64 mile) time trial, averaging over 43 km/h (27 mph). All these rides, and many more, were on René Herse cranks. I asked them whether they ever had problems with their cranks or chainrings, and the answer was: “No.” If Herse cranks were stiff enough for the combined forces of these two riders, they will be fine even for the most powerful racers.

Speaking of powerful racers, here is Geneviève Gambillon on the way to winning the 1972 world championships, on a René Herse bike with Herse cranks. She was known for her powerful sprint, and she used it to devastating effect at the world championships. She repeated her performance two years later, winning the 1974 world championships in Montreal. (The photo is taken from our book The Competition Bicycle.)
René Herse cranks has proven themselves over decades and millions of kilometers of hard riding. We are confident that the new production will be at least as reliable.
So why do other makers use more arms on their spiders and larger bolt circles? That is a topic for a separate post: stay tuned.

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René Herse Cranks

Compass Bicycles and René Herse Bicycles are proud to introduce a modern version of the classic René Herse crank. The new crank will be available this fall.
Some products are hard to improve; they make you wonder why all components are not made that way. The classic René Herse cranks are like that. Here are some of the features that make them stand out:

  • Three-arm spider to support the chainrings: Most cranks today use four or five arms, but they only add weight. Three arms support the chainrings well. Two arms would not be enough, since they do not triangulate the chainring support. (If you wonder whether three bolts can handle the torque of a strong rider, check out this Renault Alpine sports car. Its wheels attach with three bolts each.)
  • 70 mm bolt-circle diameter: Herse determined that a 24-tooth chainring was the smallest chainring that riders might want. This determined the bolt-circle diameter of 70 mm. All chainrings have the same bolt-circle diameter.
  • Single, double or triple: One, two or three chainrings can be bolted to the spider. There is no need to buy new cranks if you want to go from a double to a triple chainring setup.
  • Unlimited chainring combinations: Since all chainrings have the same bolt circle diameter, you can use any chainring combination from 24 teeth upwards. Most cranks today use bolt-circle diameters that make it virtually impossible to set up useful combinations like 48-32 or 46-30.
  • Light weight: With only three arms on the spider, only three chainring bolts, and a smart overall design, the Herse cranks are very light, lighter even than carbon-fiber Campagnolo Record cranks.
  • Low tread (Q factor): Most classic Herse cranks were between 130 and 140 mm wide, even with triple chainrings.
  • Great reliability: Herse cranks have been ridden to world championships. They were used on tandems that climbed the 15% hill of the Poly de Chanteloup hillclimb race in the big ring. Over decades of hard riding, they have proven extremely reliable.
  • Elegance: Highly polished, with a beautiful circle pattern formed by the arms and chainrings.

The new cranks are faithful to the original design in most points. Over 2 years of research and development, we have modernized the cranks in ways that Herse might have done as well, if the technology had been available back then:

  • 6066 forged aluminum arms: This alloy offers most of the strength of 7000-series alloys without that material’s risk of stress corrosion cracking.
  • 7075 CNC machined chainrings: This high-strength alloy greatly increases the lifespan of the chainrings. The rings are clear anodized for protection against corrosion.
  • Gently curved arms: While preserving the classic appearance, the slight curve of the arms (see photo above) provides extra ankle clearance. (Modern CNC machining makes it easier to create curved forging dies, which would have been difficult in Herse’s day.)
  • JIS square taper bottom bracket: The curved arms use a shorter, and thus lighter, spindle (110 – 113 mm for double; 121 – 126 mm for triple).
  • 22 mm extractor: The standard tool to remove the cranks is in almost every cyclist’s tool box.
  • Compatible with 10-speed drivetrains. A little extra space between the arm and outer chainring provides room for the “sculpted” cages of most modern front derailleurs. Moving the arms slightly outward also keeps the chain from hitting the end of the crank in the largest gear with modern, wide cassettes. As a result, the new cranks’ tread (Q factor) is slightly wider than that of the originals: about 142 mm for a double. This still is lower than most cranks available today.

The new cranks will be available in the Fall with a large range of ring sizes from 24 to 48 teeth. We will offer the cranks with single, double and triple chainrings, as well as a tandem model.

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