| Race Head Kits For any of you guys who race there bikes in stock class, i have a couple of cylinder / piston kits available. these cylinders come factory stock with larger transfere ports than the Z1 cylinder, the rpm difference between these two cylinders will definetly out rev the Z1 by atleast 500 rpms, so if you think your stock race bike is going really good, it will go alot better with this cylinder and its totally legal for stock racing. the price is only $50. this includes cylinder, piston, rings, pin, clips. from RD Racing |