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Brake Parts
Cooling Parts
Drivetrain & Transmission Parts
Electrical Parts
Engines Parts
Exhaust Parts
Foot Controls & Pegs
Frame & Body
Fuel Parts
Handlebars & Controls
Ignition System Parts
Mounts & Hardware
Performance Chips & Programmers
Racing Exterior & Body Parts
Starting & Charging Parts
Suspension Parts
Windshield & Fairings
Repair Manuals
S&S has been building big bore kits since the 60s and has it down to an absolute science. Our latest efforts are aimed at the Milwaukee Eight® platform (2017 and newer big twins) and open up a whole new level of performance for these engines. Combining a new design forged piston with their 4.25" cylinders to net a tire melting 131 cubic inches when paired with their 4.625" stroker crank. We build our big bore kits and cranks to much tighter tolerarances and with higher quality materials than the factory parts. This new piston/cylinder kit will be a solid platform for massive power.
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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