pinion too small and spur too big.

try this out. http://scriptasylum.com/rc_speed/

generally people shoot for 40 - 45 mph for general bashing.


Also here are a few general guidelines i follow:

Everything is wack. Recheck your set up!
Motor - hot
ESC - hot
BATTERY - hot

GEARED TOO HIGH
Motor - normal
ESC - hot
BATTERY - normal

GEARED TOO Low - motor is spinning too fast
Motor - hot
ESC - normal
BATTERY - normal

Insufficient batteries.
Motor - normal
ESC - normal
BATTERY - hot