Old 11-06-20, 04:41 PM
  #32  
LV2TNDM
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Bikes: Cannondale tandems: '92 Road, '97 Mtn. Mongoose 10.9 Ti, Kelly Deluxe, Tommaso Chorus, Cdale MT2000, Schwinn Deluxe Cruiser, Torker Unicycle, among others.

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Originally Posted by conspiratemus1
”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.
I appreciate your post, especially in reference to empirical data and objective observation and conclusions.

Well, let's see. You get behind the hypothetical coal truck and realize your options:
1) Pass the truck and continue your descent as normal.
2) Pull over and wait for the dangerous condition(s) to pass.

Why on earth would you, on a loaded tandem, knowing what you know about tandems and brakes, then choose to ride your brakes behind said coal truck until your hydraulic fluid boils and your brakes fail? Would you ride the brakes down a hill in a car under the same circumstances?

If so, your problem is not your brakes, but your inability to use them, lack of braking knowledge, and inability change behavior based on current conditions. This does, however, place a higher burden on the riders to know the pitfalls of tandem braking on extended descents. Should the consumer be expected to have a higher level of proficiency? I guess only the lawsuits and courts will decide.

I find it rather funny that this issue is under such heated debate with a "new, really awesome technology" that replaces the tried and true drag brake. Sometimes we don't evolve after all.

PS Ha, ha! Spot the pun!
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