So how did you know it had steel forks? Was it in the ad?
I went to the automotive department. Picked up one of the long rods with the magnet on the end for picking up droped screws, nails bolts, etc. Walked it over to the bicycle department and tried to stick it to the forks. Yay, it stuck! If the forks are aluminum it wont stick.
Gary, I've just been having a close look at your pictures and you might want to get your magnet out again as those dropouts on your forks might be cast alloy, as I think they look far too thick and chunky for steel
(but you'll probably prove me wrong):
Although the fork stanchions
(tubes) are obviously steel, I'm guessing those dropouts and sliders may not be.
When a hubmotor conversion is fitted, the dropouts are subjected to an incredible amount of spreading force from the flats on the axle as it tries to twist due to the amount of torque that has to be transmitted through it during acceleration and regenerative braking.
Alloy dropouts, although usually thick, are not very forgiving and a have a tendency to eventually crack due to fatigue
(see attachment) and generally break off completely, rather than the slot just spreading open enough until the axle is able to spin.
A spinning axle will cause damage by ripping out the wires as it spins, but hopefully the axle will still remain located within in the widened dropouts due to the weight pushing down upon it.
However, a broken dropout may allow the axle
(complete with front wheel) to fall out completely!
From past experience, riding a bike without a front wheel is almost guaranteed to end up with the rider meeting the road face first,
and this is why I would strongly recommend that a torque arm should always be fitted on a front hubmotor conversion.
Although steel dropouts are usually much stronger, they are not designed to withstand any torsional force from the axle whatsoever, and in extreme cases, metal fatigue can cause some steel dropouts to break at the joint where they are welded/brazed into the fork legs.
AlanP.S. I just noticed in the above picture that your front disc has been fitted in the wrong direction of rotation and is missing a fixing bolt too!
