Black wrinkle painted with highlighted fins. Will upgrade your stock 96″ or 103″ engine to 124″ capacity. Kit comes complete with stroker flywheels, big bore cylinder & flat-top piston kit that gives a 10.8:1 CR with the included 91cc high flow heads. The 640 Easy Start gear driven cams provide the lift required to let this engine breathe but insures easy turn-over with stock starter & battery. Note 1: Stock cases must be machined to accept the larger 4-1/8″ big bore cylinders. Kit adds .096″ to engine height. Note 2: You will build a serious high performance engine. It is therefore not compatible with stock ignition and stock (too small) throttle housings. A large throttle housing, as the 558678 S&S 58mm single bore unit, and high performance ECU is required. Carbureted engines will require a ignition system with adjustable advance curves and large carburetor, as the S&S Super G or similar. Kits are machined to be compatible with stock length manifolds. Note 3: S&S recommends MCS 978519 JIMS crankcase bearing insert, for 03-17 Twin Cam models, to replace the stock roller bearing for the stronger early style Timken bearing. See MCS 978517 for required JIMS tool. The correct Timken bearing can be ordered as MCS 508960 / OEM 9028.