i am wanting a little more pep for the bike sure it is dam fast as is but just want to improve on that what is the best bang for your buck? i do some trail riding and alot of drags down dirt roads it seems right now that there is a fuel shutoff in 4th gear or is it just revved out? feels like it has more left but just governed somehow anyways what is the best recommendation for the bike? new exhaust? new sprockets? please any input is great!