Re: SRAM front drum brake hub
Giving this more thought and after reading your comment about having too much front brake, I'm of the opinion that your idea will work just fine. As for the size of the front sprocket I have to sit down with my calculator and do some figuring but my first thought is that the size of the sprocket will not have much effect on braking action. The most significant feature will be the mechanical advantage provided by the brake lever at the handlebars. As you're aware length of pull will not be the important fact here but the length of the lever itself will dramatically impact the braking action. Have you examined the rotation of the coaster brake/sprocket when applied and how much travel will you need to duplicate what you get with the backward pedaling motion used it that design? It's been a while since I've ridden a coaster brake equipped bike but as I recall you could back pedal quite a way before applying the brake; maybe a half pedal crank revolution or so. There seemed to be a lot of free-play in the coasters. Nevertheless your system could be set up to take out the free-play and run with the brake almost applied but not enough to create drag. Just some food for thought. Keep us posted. I still really like this concept and the image I have in my mind of how it would look. Very cool and mechanical.
Age and Treachery Will Always Triumph
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