Zipper’s Muscle 124 & 128″ Kits for the M8 produce great power across a wide RPM range!

Our 4.250″ bore drop-on cylinders are fitted with Zipper’s-designed forged pistons and topped off with Zipper’s Stage III head work featuring CNC porting, +1mm stainless valves and hi-lift springs. Our Red Shift 552 cam delivers HUGE torque as soon as you open the throttle, and carries it across the RPM range to provide instant acceleration from any RPM. Compression is set to a relatively modest 11:1. It has an amazing sound at idle and under load, with torque and horsepower at the 150’s level.  Peak torque starts at 2,800 rpm – 50 pounds more than stock, staying at nearly 150 ft/lbs for over 2,000 RPM, right where you ride!  Tire life not guaranteed!




Not legal for sale or use in California on any pollution controlled motor vehicle.
Not legal for sale or use on any EPA pollution controlled motor vehicle.

*To ensure you enjoy a premium experience, Please fill out a Build Sheet/Job Order Sheet prior to completing an order on the website.
Click here for Zipper’s Build Sheet/Job Order Sheet

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