Old 05-17-16, 08:32 AM
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Bikes: 2015 Workswell 066, 2014 Dawes Sheila, 1983 Cannondale 500, 1984 Raleigh Olympian, 2007 Cannondale Rize 4, 2017 Fuji Sportif 1 LE

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Originally Posted by Luis G. View Post
Good hydraulic disk brakes are many times more powerful than rim brakes this has been proved time and time again in mountain bikes.
Care to post the numbers?

Good hydraulic discs are only better off-road because they work instantly in severe conditions---conditions which most road riders would never see (ride a lot in two-inch-deep mud on the road?)

I have a disc-equipped MTB, and road one with canti brakes for many miles. I have decades of road-riding experience. I am not just making stuff up to win an Internet debate. "Many times more powerful" is gross hyperbole. If it "has been proved time and time again" I'd like to see the "proof."

Originally Posted by Luis G. View Post
The only real benefit I see from disc brakes is the hydraulic modulation you can get. Not so much braking power.
Yup ... pretty much widely understood.
Originally Posted by Luis G. View Post
The reason why race cars use ceramic is due to heat build up. Race cars can in extreme situations heat up steel rotors to temperatures that would ruin heat treatment and but more commonly they just greatly reduce performance as they heat up.
Ceramic and also carbon fiber, which dissipates heat even more quickly ... and also need to be heated to very high temperatures to even Start working. Auto racing fans have seen lots of cars go off because cold brakes couldn't haul the car down enough after a start or restart.

Bikes have more of an issue with fluid heat, not rotor heat .... because bike rotors are right out in the air, and not anywhere near mechanical components which themselves generate enormous heat.

Bike rotors are steel because aluminum in those dimensions wouldn't be sufficiently rigid, which would cause the brakes to drag on the pads. heat build-up is not ever a performance issue.

Really though, the whole debate comes down to this:
Originally Posted by Campag4life View Post
Then what's the beef? Sharp edges on rotors is the issue. Cost aka potential for lacerating a rider in a crash which happen like clockwork in the peloton versus a fractional improvement of braking being the benefit.
Right now there is no evidence that discs will cause more injuries, but that is the only real sticking point.

The tiny amounts of added drag and weight are insignificant if every bike has the same brake system and is at the same minimum weight. The difficulty of wheel changes could be addressed through UCI rules determining universality among systems in UCI competition.

The real issue isnít stopping power. Discs are so marginally better right now that it is like the debate over removing the weight of three atoms from your bike to go faster. Discs are only an issue because the manufacturers want to sell them on commercial bikes.

Potential injury is the only reason not to use discs ... and only real-world testing will establish whether or not the dangers are real.
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