theres a million builders out there, you gotta find the one that suits you. A +4 crank will give you more low end torque, a plus for riding the trails, but the banshee isn't really a trail bike. Your gonna have to hit your pipe, port, carb combo dead on because your going after two totally different extremes. Ones low end torque and the other is a top end screamer, somewhere you gonna have to compromise.