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by jl2718 971 days ago
I switched to tubeless on rim brakes and had a downhill blowout from pressure cooking the sealant. I also tend to abuse my rims and rarely true them, so my brakes are always loose or rubbing. Both these problems may go away with carbon rims, but pincher brakes with carbon pads don’t have much stopping power. Discs do, but they are heavy and put extra torque and heat stresses on the frame, as well as a twisting moment to the straight spokes on the front, which they obviously weren’t designed for.

Okay, ready for a new idea I just thought of? Hydraulic rim brakes. They are built into either side of the fork and push bigger pads into deep carbon wheel surfaces for as much braking power as you want, with the torques applied to the strongest points of the wheel and frame, and no twisting moment applied to the spokes.
3 comments
scheme271 971 days ago
Disc brakes are preferred if you have carbon wheels. You need special pads for braking on a carbon surface and carbon fiber is much less resistant to abrasion from the braking pads. The net result is that you need to replace your expensive carbon fiber wheels much more quickly and your braking performance is much worse because brake pads for carbon fiber don't let you stop as quickly as regular brake pads. Much better to have the wear and tear from braking occur on a $20 rotor that you can easily replace.
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gomox 971 days ago
https://www.magurausa-shop.com/product.htm?pid=117393&cat=11...
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jl2718 971 days ago
Yes, very cool. I like the dual piston actuators, but that caliper structure seems like a limiting factor or point of failure. Also, it has to mount somewhere. It would seem natural to integrate it with the fork, so I looked up what they did with TT forks and came up with this single-piston dual-cantilever design as a separate component the P5 [1]. I was thinking of an internal fork mount for the hydraulics, a much larger pad, and a rim specially made with a wider braking surface. Somebody must have tried that in a concept design.

1. https://www.bikeradar.com/news/magura-rt8-tt-first-look/

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frabbit 971 days ago
Saw this after I posted my comment. I first came across Magura on German commuter bicycles. A good, reliable brand.
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frabbit 971 days ago
Magura have been making hydraulic rim brakes for German bike assemblers for at least a decade.
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