Saturday, July 21, 2012

Toggle Heim...

I sometimes neglect the blog because I have been posting quick photos and simple posts on the Black Mountain Cycles Facebook page.  I realize that there are some folks who aren't on Facebook (and for that, I applaud you).  So, I need to try to remember that and post some more here.  

With that in mind, here's a quick one of a super-rare toggle-cam that was created by Charlie Cunningham in the mid 80s.  The cam is a two part that is width adjustable.  The width is adjustable so that the upper cam bump can be fit to the roller at the proper location.  The roller needs to be just on top of the upper bump so that when the lever is pulled, the pads travel to the rim quick and then the roller is on the lower ramp where the brake modulation and power are dialed.  By altering the cam shape, the brake's power can be altered.  The beauty of this design is that you can get true one-finger braking that is super easy to modulate.  

The fixed point of the cam on the brake arm is secured via a clever Heim joint.  This allows the cam to be pivoted out of the way when it is disengaged when removing the wheel.  There are only a small handful of these clever toggle-cams that were created by Charlie back in the 80s.  




(What's playing:  Tour de Fance time trial.)

1 comment:

rigtenzin said...

Beautiful! I had a bike with the Suntour roller cams, so I'm always interested in your roller cam posts.