4in. Stroke Flywheel Assembly. Fits Twin Cam Softail 2003-2006.

Features & Benefits:-

* Heat-treated 4140 material is harder & 114% stronger than stock.

* Harder material, eliminates thrust washer.

* Larger 1.671" diameter 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 and 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 available power!

* Trued to with in .0005" TIR

* Rod Bearings have 20 rollers vs 18 stock

Tech Tips:-

* 2003-2006 motors can be upgraded to the stronger "Timken" crankcase bearing. Part # SS320-0397

Proudly Made in the USA by S&S Cycle !