Bolt in - no machining, balancing, or splitting the crankcases; install can be performed with engine still in frame. Cast Ductile Iron Sleeve in cast aluminum for superior heat transfer. 88in. engines are boosted to 100in. 96in. and 103in. engines are boosted to 110in. 10.5:1 compression (w/ stock 85cc heads) makes for a very streetable and dependable engine that also responds well to performance cams. Complete kits include cylinders, forged pistons, rings, piston pins, clips and gaskets. Available with wrinkle black or silver powdercoat finish cylinders. NOTE: Not for use with S&S 79cc heads.