Spreading a front fork

John Galvin

Pedelecer
May 14, 2014
77
2
51
My ebike kit is on the way and I'm going to be fitting a front hub motor to a Tern Link P9, which has
already been fitted with a steel front fork.

I'll be using a threaded bar and two bolts to spread the fork by around 10mm to make the motor fit. Do I need
to worry about the two legs of the fork spreading at different rates or can I assume that each leg will spread
by the same amount?
Is there anything I need to do to guard against this happening?

Thanks
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,669
it won't take more than 5 minutes and there shouldn't surprises with a steel fork.
 
D

Deleted member 4366

Guest
If one side goes more than the other, whack it with a mallet until it's central. Steel forks bend very easily. Threaded bar is overkill. You'll probably be able to do it with your bare hands.
 

muckymits

Esteemed Pedelecer
May 31, 2011
419
2
While on the subject of fork spreading would like every ones opinion on spreading a rear fork (ally) 25/30 mm?
 
D

Deleted member 4366

Guest
It should be possible as long as there's not too much bracing. I stretched a Rocky Mountain rear sub-frame close to that. I tested a scrap alloy frame a while ago. I just put my foot on one side and gave the other a good heave an it set about 25mm wider at the first attempt.