Thumb operated rear brake

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GRIM

Race Dog
Joined
Feb 16, 2007
Messages
3,221
Reaction score
454
Location
Underberg
Bike
Honda CRF-250L
Getting on my trials bike again has been great, but the one thing that I realised is that occasionally, a rear brake is needed. And then you REALLY need it...
For those that don't know, I had an altercation with a taxi last year, and one of the results is that my right foot no longer works. As a result, I needed to come up with a solution for my rear brake.
I looked at all of the off the shelf solutions, i.e. the rekluse , clake, etc, as well as the cable actuators for the foot lever, but none of them really worked fro trials, as in most riding circumstances the clutch is predominantly an on/off thing, whereas in trials the clutch is about one of the most important controls, and all the front mounted levers tended to get in the way of the clutch control.
After a lot f head scratching and playing around with a lot of different scenarios, I reverse-mounted a front brake master cylinder to the left hand side, and machined an offset lever to position the paddle underneath the grip where I can press it with my thumb, leaving my fingers free to operate the clutch. I had a new pipe made up to connect it directly to the master cylinder, and removed the foot brake master cylinder.
Below are some photos of the first working prototype. It works well enough for now, I must just tidy it up a bit to get it through the scrutineering regulations. I could possibly use a bit more leverage, but there is not enough handlebar real estate to move it any further over, so I am will also play around with shifting the whole assembly down and over on an offset section of tubing. But for now I'm enjoying riding downhills again  ;D ;D
 

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