the need for speed

[xxxlosi]

Hi i have a d4 motor in a xxx. The d4 motor is 13t double wind. I have a 78/21 setup in now but i need it to go just a couple miles and hour faster anyone got any suggestions on what gears to put in to make it faster. I don't need that much torque and i want more top end speed.
Thanks

[guggi101]

Ok make then gear on the axle smaller by a few teeth or make the gear on the motor larger by a few teeth.

[XXXER]

Get your comm cut, and give it a fresh set of brushes, for maximum performance, and very fast wear, use Trinity 4380NT brushes.

The other way to get both of those you said, are batteries. Better batteries are the way to go.