This kit simply upgrades your old Trail Bikes Race Head 88cc or 108cc kit to the new head for additional performance. Fits many other bore kits. Always check piston clearances when installing.
Race Head – Larger valves (now 25/22mm) and better flow for increased performance. Also has bigger cooling fins. Includes all necessary parts and comes assembled! The exhaust valve has been upgraded to stainless steel (21-4N material). Includes 52mm piston kit.