Note:
This S&S 4-1/2in. stroke flywheel assembly when used with 3-7/8in. cylinders creats 106 cubic inch’s
1. Purchase S&S 3-7/8in. piston kit # SS92-1210 & bore your current cylinders
Features & Benefits:
* 2003-2006 motors must be upgraded to the stronger Timken Crankcase Bearing & Sleeve # SS31-4013 & JM-956
* Heat-treated 4140 material is harder and 114% stronger than stock.
* Harder material, eliminates thrust washer.
* Larger 1.671in. diam eter crankpin.
* Designed with increased cross-sectional area for increased crank-pin clamping force – No welding required.
* Integral mainshafts – Eliminates two potential points of weakness.
* Consistent balance & precision machining – Truer flywheels & less vibration.
* Reduced mainshaft deflection at high rpm – less vibration, reduced piston & rod side thrusting, prevents oil pump damage, fully compatible with gear drive cams.
* Capable of higher rpm – More avai lable power!
* Trued to with in .0005in. TIR
* Rod Bearings have 20 rollers vs 18 stock
Proudly Made in the USA by S&S Cycle !
Additional Parts Required:
* SS92-1210 – S&S 3-7/8in. Piston Kit
* CG-C9892 – Gasket Kit
Tech Tips:-
* Piston jets (SS31-2026) included
* Compression ratio w/OEM heads = 10.1:1
* Compression ratio w/S&S 89cc heads = 9.8:1
