129" Power Package Engine Performance Kits / '17-'23 107" M8 Oil Cooled Motors

The S&S 129" Power Package takes a '17-'23 oil cooled M8 from 107 to 129 cubic inches as a bolt-on, bundling the big bore kit with a complete cam chest.

No Shipping to California.

A big bore kit alone raises displacement and then asks the stock oiling system to keep up with it. This package does not make that assumption. Alongside the 4.32" bore and 11:1 forged pistons, it replaces the oil pump, cam plate, cams, pushrods and tappets, so the supporting systems grow with the motor. Original engine serial numbers stay with the bike.

What Comes in the 129" Power Package

The oiling side is where the money goes. An S&S oil pump and cam plate in blue anodized finish carry removable passage plugs and independent scavenge sections for the flywheel cavity and cam chest. A debris screen sits in both scavenge pickups and a magnet in the cam chest, keeping particles out of the pump before they cause damage. Oil flow capacity is increased on both feed and scavenge sides, and an adjustable pressure relief valve lets oil pressure be set without disassembling the engine.

S&S 550 cams are specified for big bore applications, matched with valve springs rated to .605" lift and Quickee pushrods with chrome tubes. Premium S&S tappets complete the valvetrain.

129" Power Package Specifications

• Fits '17-'23 oil cooled M8 107" motors
• 129 cubic inch final displacement, 4.32" bore
• 11:1 forged pistons
• S&S oil pump and cam plate, blue anodized, with removable passage plugs
• Independent scavenge sections, debris screens and cam chest magnet
• Adjustable pressure relief valve
• S&S 550 cams with valve springs rated to .605" lift
• Quickee pushrods with chrome tubes and premium S&S tappets
• Drive options: chain drive or gear drive
• Finishes: wrinkle black with or without highlighted fins, chrome or black pushrod tubes

Professional installation is recommended. ⚠️ VERIFY that your motor is an oil cooled 107" M8 in the '17-'23 range, since this package is specific to that engine. Retuning is required.