Originally Posted by
Mark Kelly
The braking force causes the rim as a whole to push back on the hub, this force is carried via the spokes. This force will cause the leading spokes at the top of the wheel to wind up whille the trailing spokes unwind, moving the rim to the leading spoke side.
At the bottom of the wheel the reverse is happening, so it moves to the trailing side. Net result is that the angle of the wheel to the hub changes with braking force = very bad handling characteristics.
Draw a diagram (I sound like FBinNY talking to me a few months ago). Using this questionable lacing pattern on a rim braked bike will not cause the hub flange to twist as you have suggested during braking. What you are suggesting will happen if applying torque to one side of the hub (rear wheel or disc braked wheel). During rim braking, the leading and trailing spokes facing the back of the bike at the time will receive an increase in tension while the spokes facing forward will decrease in tension. This is due to the counter force being applied to the hub by the fork as it tries to slow the bike. However, what's different in this scenario from a standard wheel is the since there are only leading or trailing spokes on each side of the hub, the hub shell receives a torque as the spokes pull in opposite directions on the hub (whereas with crossed spokes, you'd have equal numbers of leading and trailing spokes pulling in opposite directions on the hub on both sides of the hub with a net torque on the hub shell equal to 0).