Zipper’s Sleeper 103 kit ‘07-‘13 Twin Cam® engines

Zipper’s Sleeper 103 kit is an easy and affordable upgrade for 2007-up 96” Twin Cam® engines. Your cylinders are precision-bored from 3.750” to 3.875” with forged 10.25:1 pistons to boost displacement to 103”, while your stock cams are replaced with your choice of our Red Shift 525 or 528 grinds. The 525’s are designed for heavily loaded bikes and build huge torque just off idle with less top end power, while the 528 cams shift power and torque to the right, across the entire RPM range with stock heads. Gain even more power with (1) Zipper’s optional Stage 1 headwork and (2) improve longevity with critical oil system blueprinting by adding our cam chest upgrade that includes our billet cam plate, dual-piston cam tensioners, full-compliment cam bearings and quality USA lifters. With power peaking at 5,000 RPM, this kit is a great choice for the rider who rarely pegs the throttle to red line, but rather enjoys the super-strong pull of low & mid-range torque!

This kit uses your factory cylinder (and heads if Stage 1 option is chosen) cores sent in for modification. An exchange may be possible once your cores are cleaned, inspected and qualified for exchange.
*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

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.

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