Rene Herse Headset Slip Ring

Among the ingenious features of top-of-the-line Rene Herse bikes are the internal lighting wires. Not only do the wires run inside the rack and frame tubes—the electricity for the taillight is actually transmitted through the headset, so there are no external wires connecting frame and fork. 

The clean appearance is just one advantage of this system. External wires can get snagged and broken, but internal wires are protected and last as long as the bike. External connectors spliced into the wire that goes from the fork to the frame are exposed to the elements, and often stop conducting electricity after a few years of year-round riding. 

The internal slip ring, developed by René Herse in 1946, eliminates the wire connecting frame and fork. In addition to protecting the wires, it makes it easy to remove the fork, for example, when packing the bike Rinko-style. Classic Rene Herses used a fragile carbon brush that was easy to damage if the fork was removed without proper care. (These bikes were intended to be serviced only by the Herse shop.)

Today’s version uses a strong brass brush. The slip ring is also made from brass and reinforced with a lip to keep its shape when it’s pressed into the head tube. The ring and insulator are designed to provide an easy path for the brush to slide in and out of the head tube when the fork is removed or installed. The system includes the brass slip ring, insulator ring, spring-loaded contact brush and holder (which is brazed into the steerer tube), plus shrink tubing as insulation for the contact brush.

Pro Tip: The head tube needs to be reamed out 15 mm above the upper edge of the headset cup. Make sure your headset reamers is long enough, or use a head tube that does not need significant reaming.