Braking Technique

Braking Technique

For an article in Adventure Cyclist, I needed a photo on braking technique, so my children and I went to a steep hill in Discovery Park. They rode up and down the hill while I snapped photos. Even though the photo above has a little speed blur, I like it so much that I want to share it with a wider audience. You really can see how braking on a bike works:

  • The front tire compresses a lot as the inertia of bike and rider put most of the weight on the front wheel.
  • The rear wheel is barely touching the ground.
  • To counter this forward weight transfer, the rider pushes his body backward.
  • He locks his arms to prevent going over the bars. (Cyclists go over the bars not because the bike rotates around the front hub, but because they fly forward when the bike slows down.)
  • He picked a line on clean asphalt away from the mossy edge of the road for better traction.
  • With good traction, the rider uses only the front brake. (The rear wheel is barely touching the ground, so any braking there would cause a skid.)

Add to that powerful V brakes and grippy tires, and it’s amazing how quickly a bike can stop. I am glad my children have practiced braking hard. Hopefully, it will be instinctive when they need to stop in a hurry.

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Comments (13)

  • Keith Snyder

    What a great picture. What we all love about bicycling, kids still show on their faces.

    April 13, 2011 at 7:48 am
  • Bill

    Learning how to operate a bicycle properly at his age will ensure that he has hundreds of thousands of pleasurable biking miles in his future. Too many people believe that all there is to riding a bike is being able to balance.

    April 13, 2011 at 1:07 pm
  • Jim

    It looks like the rear tire is touching the ground enough to show compression. As long as the rider can get his butt back and low, both brakes can be applied forcefully without skidding on good, clean pavement.

    April 13, 2011 at 2:56 pm
    • Jan Heine, Editor, Bicycle Quarterly

      The rear tire should touch the ground, but if you can brake on the rear without skidding, this simply means that you aren’t braking hard enough on the front. The exception is when traction is limited: Braking hard on the front can overwhelm the adhesion of the tire, causing a skid. Since your braking is limited anyhow, the weight transfer to the front is reduced. Using both brakes doubles your traction on the road, and thus reduces your stopping distance.

      April 13, 2011 at 3:40 pm
      • Jim

        This simply isn’t true. If you get way off the back and have your butt nearly touch the tire, and you have fat tires not overinflated, and are on level ground with a clean surface, and you have extremely strong brakes with the right technique you can stop on a time with no skid from either tire.
        This is a very common mountain bike technique.

        April 13, 2011 at 3:47 pm
        • Jan Heine, Editor, Bicycle Quarterly

          Mountain bikes usually have knobby tires and are ridden on dirt, so traction is limited, and using two brakes doubles your traction. On pavement with good brakes and grippy tires, maximum stopping power comes from the front brake. That is the reason why powerful motorbikes have two huge front disc brakes and one much smaller rear disc.

          April 13, 2011 at 4:16 pm
  • Jim

    Not refuting where the most of the stopping power is. The mtb technique applies to the road as well, not necessarily the other way. Moto racers use their brakes in conjunction with each other, the rear stablizes the chassis and applies some stopping power. The same applies to bicycles to a lesser extend due to large weight differences.
    Locking the elbows isn’t the only way to not go over the bars. The ability to transfer weight to your feet and to activate the core are more important.

    April 13, 2011 at 4:54 pm
  • Tom in Portland

    I agree with both the mountain bike and motorcycle examples. When stopping, weight transfer to the front wheel occurs. I see the issue as movable ballast. The cyclist can move a substantial portion of the total weight, as ballast, to the preferred extreme rear position. This allows more total weight on the rear wheel. Compare this to the motorcyclist’s body which is a lower portion of the total load, and is limited in body position changes. On the bicycle, with the increased rear load, there is increased friction at the tire to road surface interface, which allows increased braking power. This problem is similar to those used in my statics and dynamics courses for mechanical engineers way back when slide rules were used by calculators to solve equations, and prove the results. But that is a story for another day.

    April 13, 2011 at 9:50 pm
  • Tim

    Great post. There is a school of thought – I think it was advanced by Sheldon Brown among others – that a rear brake may not be necessary at all for the reasons detailed. While I absolutely agree with the physics of stopping quickly using primarily the front brake, it is not without problems in particular circumstances. In the not so distant past I had the front wheel lock up on a slippery zebra stripe causing a serious crash. And on my racing bike with very short wheel base I managed to flip over the handlebars three times in the past two years. Each time this occurred at slow speeds when my center of gravity was far forward. No doubt had I had my butt back behind the saddle these mishaps would have been avoided.

    April 13, 2011 at 11:31 pm
  • Drew

    I use the rear brake for slowing down, which is 98% of my braking.
    I add the front brake during steep hill braking; or during a rare emergency stop.
    This became habit decades ago, after a crash or 2 and a few close calls on mossy surfaces made me cautious of front brake use.

    April 18, 2011 at 8:20 am
    • miconian

      This is what I’ve always done as well, and how I learned to brake as a kid. I was just too uncoordinated and unbalanced to seriously attempt to use the front brake as my main stopping tool. I think of the front brake as what you use for actual, final stopping, after you have slowed to a near-stop with the rear brake.

      April 22, 2011 at 10:15 am
      • Jan Heine, Editor, Bicycle Quarterly

        To get a feel for the traction available during front braking, I recommend experimenting on dirt or snow. There, the break-away is less sudden, and you develop a feel for the messages your front wheel sends as it nears the limits of adhesion.

        April 23, 2011 at 6:15 am
  • Mark Petry

    Also emphasize that you should not be turning if you’re doing meaningful braking! A bike in a turn is applying its breaking forces thru a distorted contact patch – if you skid the front wheel, you’re going down. Do all your braking while riding in a straight line. Also – powerful braking requires brakes with good mechanical advantage, good friction properties pad – to – rim, and the ability to smoothly modulate from initial application to just short of lockup. One of the complaints I have about disk brakes is that they can be “grabby” – it’s hard to apply them smoothly, as their self energizing behavior causes the initial application to be too severe. On a bike, this can spill you!

    April 22, 2011 at 10:22 am

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