Originally Posted by NickK3
Disks have the interesting effect that they require even the front wheel to be dished... after all the work to diminish or eliminate dish in the rear wheel (I have Ricthey OCR's on my road bike and love them), now we are dishing the front?!
No worries...
1. The forces acting on a rear wheel are several degrees of magnitude higher than a front wheel.
2. The overall strength & durabilty of any wheel still comes down to matching the right design (i.e., number of spokes, type of spokes, lacing pattern, & flange height for a given team weight & intended use), with quality components and the skill / attention to detail of the wheel builder.
3. As you note, Ritchey and Velocity sell off-center rims (OCR) that can be used on a front wheel to mitigate most of the front wheel dishing effect.
If that's not enough, consider that those of us who have been slamming the wheels of our dual-disc equipped off-road tandems into rocks, ruts, trees and berms for many years now have been using 32h and 36h non-OCR rims without any major wheel durability issues. It might also be worth noting that the rear wheel spacing on some of the most popular "extreme" F/S off-road tandems feature 135mm rear spacing which, when combined with rear disc brakes, makes for some really shallow bracing angles on the rear wheels. Again, most of us have never been stranded by spoke failures -- just imploded Hugi, Coda, and Shimano cassette hubs, torn-off rear deraillers, folded cassettes and otherwise busted drivetrains.
Just some food for thought and, yes, the physics acting on 26" fat-tired bike off-road are very different than the ones acting on a 700c skinny-tired road bike. But, torque is torque and the sideloads off-road far exceed anything a road bike's wheels experience during normal riding.
But, to help alleviate any major fears about the newer dual-disc machines, we have several friends -- two of them tandem builders -- who have been riding dual-disc equipped road tandems for the past two seasons. Team weights range from 340lbs to upwards of 380lbs and the riding terrain has included the mountains in France, Austria, Switzerland, Italy as well as mountains in Washington State, Colorado, and North Georgia. There have been a few teething pains that have been addressed with the addition of strong return springs to improve brake feedback and modulation control, but that's about it.