S&S CYCLE 129" Power Package Engine Performance Kit — Bore 4.320", 11.0:1 – 17-25 Touring, 17-26 Trike

The 129" Power Package Engine Performance Kit delivers a bolt-on big-bore upgrade for 107" M8 engines without case machining.

• Big bore bolt-on kit increases 107" M8 to 129" with no case machining required
• Big bore 4.320" cylinder with 11.0:1 forged pistons
• S&S oil pump/cam plate
• Passage plugs are removable for servicing
• Independent scavenge sections for flywheel cavity and cam chest
• Debris screen in both scavenge pickups
• Magnet in cam chest to help prevent debris from entering the oil pump
• Increased oil flow capacity on both the oil feed and scavenge side
• Adjustable pressure relief valve can be adjusted with the unit installed in the engine
• Quickee pushrods with pushrod tubes
• S&S premium tappets
• S&S hard anodized, black coated tappet cuffs are billet aluminum construction
• S&S valve springs; work with cams up to 0.605" lift
• High performance conical single wire spring design
• HPT496 cam designed for big bore applications
• MLS (multi-layered steel) head gasket
• Includes 129 cam cover badge
• Made in the USA
• Retains stock engine height
• Works with stock crankcases
• Works with the stock and S&S roller rocker arms
• Original engine serial numbers are retained
• Compatible with the stock valve springs, both first generation (round port) and second generation (oval port)

Designed for performance and serviceability; consult an experienced installer to confirm fitment and cam selection for your application.