Calming Down a 6v Starter on 12v?

[leon bee]

I got nothing against 6 volts, I like it. But I have one little yard truck with a big 12v winch on a boom out back. So I put an alternator on the 8BA. Man, the starter really hits hard. This is a seldom used truck.

I was thinking: We always hear about using big fat wires on 6v, which I do. What if I used a long, skinny lead down to the starter. Shouldn't that weaken the starter? Harm anything? I guess under voltage might not be good for the motor.