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This kit converts 1986-'21 883cc and 1200cc HD Sportster models to 1250cc displacement. No machining or rebalancing is required. Kit contains forged flat topped 3-9/16" bore pistons with coated piston skirts, S&S 3-9/16" bore cylinders, MLS head gaskets, base gaskets, exhaust gaskets, assembly lube, and instructions. 883 cylinder heads may not be used with this kit. For the best performance CNC head porting, performance cams, exhaust and intake upgrades are recommended.
Legally, a vehicle manufacturer cannot void the warranty on a vehicle due to an aftermarket part unless they can prove that the aftermarket part caused or contributed to the failure in the vehicle (per the Magnuson Moss Warranty Act (15 U.S.C. 2302(C)).
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