Well--besides top fuel and prostock type engines we have been into karting -----your package as sold is probably pretty well optimized for what its purpose is---biking as on flat ground---higher compression in itself won't be a lot of help altho some porting changes would---porting is like camshaft changes not about the size of the port but how the vertical diminsions effect inlet and exhaust---just like cam changes tho, it really effects the rpm level where hp/torque occur

if you want to climb a hill you should be looking at adding to the low rpm range that will be happening closer to the top of the hill, not max rpm----