What size of the wire and how many turns to rewinding a high speed mini 4wd motor?

I used to rewind slot car motors by hand.

Most of the time there is no build sheet or schematic for electric motors.

What to do is measure the diameter of the copper winding wire. You can buy it maybe at a local motor shop maybe EBay?

Then as you unwind the old. Count the windings so you can rewind it the same exactly.

After rewinding. You should be able to use a meter to test for shorts.

I masked the commutator, shaft, and outer armature. Then give it a light spray of nonconducting insulating motor winding paint. Its usualy a dark red and thick.