Can a rear DD hub be modified to fit front

Jbern

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Converting a small, full-suspension dog/mush scooter to electric. 20” wheels and has 100mm width in rear (I would like to have the motor in the rear). I have a Magic Pie 20” rear hub and a Magic Pie in a 26” wheel (both are maybe 2nd generations without internal controllers) and was wondering if I could remove the freewheel(?) and make the motor fit in a 100 mm space. My other option is a front geared motor and putting it in the rear, but I have these rear DD hubs already sitting here….

If the freewheel is removed (is that possible?) will it then fit in a 100 mm space? (I’ll be using torque-arms as the rear drop-outs don’t look very thick.)

Forgive the NOOB question. And thanks.
 

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Depending on the difference in size you could conceivably pull the axle and mill down the shoulders to suit, though it's not necessarily practical to do so. Just pulling the freewheel likely isn't going to cut it.

Steel or aluminum frame? If steel you may be able to spread the dropouts to suit, though 1.4" might be a bit of a stretch. I'll have to defer to someone else on that one though.
 
I am riding a Leaf 1500W rear motor (135mm r.d.o) in the fork of my fat bike (135mm d.o.)
Yes I took out the freewheel and by eyeballing it all, it seems to be inline and not far off.
My previous fat bike (Costco) had an odd fork dropout width but it wasn't to far off.

If I had a reg mtb, then all I would need to do is buy a fat fork which is cheaper then buying a front hub motor.

Otherwise you'd have to cut down the 135mm drop outs of the rear hub to suit your forks dropout and be sure that you took the same amount off each side. I would rather just buy a cheap hub motor to fit the front.

edit - if it comes down to it you could just weld up your own fork.
 
It's less expense, time, and effort to get two new front hubs for this scooter, unless you're a well equipped machinist or you know one who'll work on your project for free.

It's not just the freewheel that makes a rear hub wider; it's the axle (which is pressed into the stator).

You could spread your rear spacing, but that's a lot of bending to ask of such a short swingarm. You might buckle the tubing or hork up your suspension pivots.
 
Thank you all for your excellent responses/information. I see that the best approach is to simply get a hub designed for the 100 mm spacing of front forks, and then mount it in the rear (where the 100 mm spacing should allow an easy drop in). Clearly not worth the headache to modify a rear hub.

Thanks again all!
 
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