Originally Posted by
Badger6
Certainly. The finned pads and oversized caliper bodies of Shimano seem well suited to this task. Their brake solutions seem to offer the best option for doing exactly what you're describing to give both the maximal power (though I bet any disc brake gets close on this) and prevent fade, which is a problem even for a one-up bike because physics is physics. . . .[emphasis added]
”Seem” is not “does”. Physics is an experimental science. Conjectures can be tested. (Which is why physicists sometimes mock the merely observational disciplines as mere stamp collecting (attributed to Rutherford whose own Nobel was in Chemistry, not Physics, likely because the Nobel committee didn’t fully grasp what he had accomplished in transmutation.)
So, people who tout new brakes need to show that they
do resist heat fade during sustained use to ******** speed on a long hill. Thorn in the U.K. and Santana in the U.S. do this in selecting brakes for their tandems. (I have no connection with either company. I do own an old Santana, with rim brakes.)
Here’s the scenario I worry about. You have a familiar long descent with hairpins connected by tangents. Conventional technique is to coast as fast as you dare in the straights, brake hard for the bends, then use the higher speed in the following straight to let the brakes cool. Fancy stuff on the brakes ought to let them cool faster when they aren’t being used, sure, so you reach the bottom under control and able to stop at the intersection. Especially with some practice on it.
Now, suppose you have to follow a loaded coal truck or a camper caravan down that hill much slower than you can coast and you can’t pass. So you are using the brakes in the tangents, too. Will their little fins be able to dissipate heat under continuous use, plus going even slower in the bends? Show me that they can. We have descended some truly scary paved roads in Europe where we really did have to brake the whole way down and stopped frequently to allow brakes, of various designs over the years, to cool. And I’m not including the marquee mountains and cols like Ventoux and Tourmalet, which don’t require continuous braking. Some narrow twisting little road in the Dolomites can be scary challenging if the bends come right on top of each other.
Thing is, as tandem teams get heavier, they become less willing and able to climb up into the high country to find these descents, so their expectations of brakes are diminished. They regard quick two-finger stopping from the hoods as an adequate test. Then they turn their tandem into an electric motorcycle and discover that they’ve still got plain old crappy bicycle brakes intended to help an ectomorphic bike racer get through a hairpin, not brakes that the loaded coal truck needs.