yean u heard me right. and no i dont use special tires. i use the dinky old moped tires. they work fine.... a little smooth at top end...:-). the other mod i did was i hogged out the case to match the cylinder and now it has a helluva lota power! i love it. the other fact is i have it jetted just perfect. sometimes if im at a stop and i slame the throttle she'll pull out right from under me. yeah that powerfull. some one else with a bore kit should match the case and cylinder and see how powerfull it is!