James wrote:
On 17/3/19 2:56 am, Ralph Barone wrote:

I missed commenting to John earlier. Your visualization of the problem
isn't quite right. With rim brakes, the spokes do not see any braking
forces, since the brakes sit between the spokes and the tire.

The spokes may not see any torque between the hub and rim, but are
certainly forces due to braking that the spokes see.


Now that I think about it some more, yes, there should be increased tension
on the rear facing spokes and decreased tension on the forward facing
spokes under rim braking. However, under disc braking, there should be an
additional torque which should increase tension on all spokes where the
head leads the nipple and decreased tension on all spokes where the nipple
leads the head (I'm sure there's a technical term for it, but it currently
escapes my mind).

I imagine that these "torsionally derived tensions" in disc applications
are greater than the spoke tension changes with rim braking.