Originally Posted by
cyccommute
The hub is free to roll, yes. The hub isn’t free to turn relative to the spokes. Applying force to the wheel through the brake system, whether disc or rim, put stress on the spokes. The hub shell (which the spokes are attached to) tries to turn relative to the spokes but the hub is locked in place. The amount of force on the spoke bed is the same in both cases. A disc doesn’t generate more force at the spoke bed than a rim brake. Therefore there is no reason for a limitation on using rim brake rims with a disc hub...aesthetics aside
Yes, but the point is that there is MORE torsional torque exerted on the spokes with a hub type brake. Sorry, but that has been something that has been accepted by people for years, in fact, Erik Buell used large rotors, mounted at the rim of his motorcycles so he could use a lighter weight wheel. The larger disc also gave better heat management, but it helped reduce the stress to the wheel, because of... torsion placed on the wheel due to braking forces. Mounting the brake disc to the rim, rather than at the hub lowered the torsion applied to the wheel. The rim mounted brake disc had many other benefits as well, but overall, it allowed Buell to reduce unsprung weight, one disc instead of two heavy discs, one caliper, and, in his own words, "
We used a totally new front wheel concept based on the idea that without braking loads being fed through the hub and back out through the spokes, then there would be no torsional loads through those spokes. That enabled us to take a significant amount of weight out of the wheel." And, it worked, very well, because, physics.
Continue debating what others have already proven. I will watch from the sidelines.