Wiseco SK1376 Pro-Lite 76.50mm 0.50mm Oversize 2-Stroke Piston Kit for Ski-Doo 550F

The Wiseco SK1376 is a Pro-Lite forged piston kit engineered specifically for the Ski-Doo 550F twin-cylinder, fan-cooled 2-stroke engine. With an actual bore size of 76.50mm (0.50mm oversize) over the standard 76.00mm bore, this kit is the go-to solution for top-end rebuilds on worn cylinders requiring an overbore. Note: oversize pistons require cylinder sleeving.

Kit Contents:

• Forged Pro-Lite piston(s) — 76.50mm actual bore
• 3.012 Semi-Keystone ring set (3012KD)
• Taper-wall wrist pin(s) — 20mm x 60.0mm non-chromed (S631)
• Round wire circlip/pin locks — 20mm (CW20)
• Top-end gasket kit

Key Specifications:

• Bore (Actual): 76.50mm
• Bore (Oversize): +0.50mm over standard
• Standard Bore: 76.00mm
• Stroke: 61.00mm
• Cylinders: 2
• Engine Type: Ski-Doo 550F (Fan Cooled, 2-Stroke)
• Skirt Coating: Moly
• Piston Material: High-silicon 4032 aluminum alloy

Why Wiseco Pro-Lite?

• Forged from high-silicon aluminum alloy for superior strength and dependability
• Engineered, forged, and machined in the USA (Mentor, OH)
• Improved tensile strength optimizes durability and service life
• Dedicated forgings with optimized strength-to-weight ratio
• Moly skirt coating reduces friction and improves heat transfer
• CNC machined cam shape and profile for peak horsepower and service life
• Precision matched and balanced for consistent performance

The Wiseco SK1376 is the trusted choice for restoring compression and performance on Ski-Doo 550F-powered snowmobiles. Whether rebuilding after high mileage or preparing for an overbore refresh, this complete kit delivers everything needed for a reliable top-end rebuild.