Having tried to rewind a hub motor. You will be really hard pressed to get optimum fill factor. It is hard enough winding the motor with its original windings!
When you double the width of the stator, you need to halve the turns to keep the same KV.
Your hands will be nice and calased by the end of the first hour let alone the end of the winding.
Measure the length of wire you need. And then add 4-7 more feet to the original length.
My last note to you, make sure you have something to keep count of the number of turns you have on each tooth. One mess up and the motor won't turn at all. So make sure you catch your mistake as it happens and not when the motor is wound up.
Here is the link to my attempt at winding a hub motor. But I did not realize how long it would take and couldn't let it interfere with classes.

. This thread probably has more pics per post than any other rewinding thread out there. I tried to document as much as I could.
http://endless-sphere.com/forums/viewtopic.php?f=30&t=43781&hilit=+Rewinding
You also have oldhaqs thread where he rewound his H40 series motor much better then mine :wink:
http://endless-sphere.com/forums/viewtopic.php?f=6&t=42361&hilit=+Rewinding
Also farfles dual pie rewind thread has some much needed details when gluing the magnet cans together.
Hope this helps good luck and god bless you
