What electronics are you using? We use the silver can motor and it seems fast enough for our off road track and enough power with the stock gearing.
One note from others who have used the tt01 is that the arms do not go down much due to the bumper/underplate. So they do not have a lot of down travel fro the jumps. Your speed control might be the problem for no locking up the wheels. They're a lot of fun!
Mike