Absolutely, I never stated that a front hub motor can be used without a torque arm. Also, the fork must be robust enough to safely endure the pull from a strong motor. Headsets must be up to the task as well. The only uses I see for a front mounted hub motor are on something like an adult trike for example, and again, probably under 500 watts.
Yes I actually did read the story of someone who tried to electrify their bike using a front hub motor conversion kit and had the wheel pulled out from the drop outs when they hit the throttle. Maybe they didn't tighten the axle nuts sufficiently. Who knows since none of us were there.
It can be done but it is a sensitive place to power the bike from is what I am trying to say.
Originally Posted by
chas58
A front bicycle fork (non through axel) is really not designed to take any torque. It doesn't take much to spin the motor in the drop out, and then you are at risk of the front wheel falling off or getting jammed up. If the fork is steel, it will bend and probably hold together. If it is aluminum (or CF) it will break and then it gets nasty. A torque arm will add a large margin of safety.