SPI .040 Over Bore Top End Repair Kit for Ski-Doo 550 Fan Cooled 2003-2020 77mm

SPI .040 Over Bore Top End Repair Kit for Ski‑Doo 550 Fan Cooled

This top end repair kit includes a .040 over bore piston, rings, and gaskets to restore compression and performance on Ski‑Doo 550 fan‑cooled engines. The kit is precision‑engineered to match OEM specifications for a reliable rebuild.

Overview

This SPI .040 over bore top end repair kit is designed for Ski‑Doo 550 fan‑cooled snowmobile engines from 2003 to 2020. It contains everything needed to refresh the cylinder, piston, and sealing surfaces after a bore job. The kit provides a cost‑effective way to bring back lost power and reliability to your two‑stroke engine.

Built For Performance

• Includes .040 over bore piston matched to 77mm bore
• High‑strength cast piston with precision ring grooves
• Complete gasket set for a leak‑free seal
• Plated rings reduce break‑in time
• Engineered for consistent compression across operating temps

Fits These Machines

• for Ski‑Doo 550 Fan Cooled (2003‑2020) 77mm bore

On‑The‑Job Use

• Snowmobile engine rebuild after wear or seizure
• Performance restoration for trail riding
• Winter utility use requiring reliable starting

Specs At A Glance

Good To Know

Q: Does this kit include a wrist pin and circlips? A: Yes, the kit typically includes the wrist pin, circlips, and all necessary seals for a complete top end rebuild.

Q: Can this .040 over bore kit be used on any 550 fan‑cooled engine? A: It is specifically designed for the Ski‑Doo 550 fan‑cooled engine with a 77mm bore; confirm your engine stamping before ordering.

Slight variation in finish or dimensions may occur between production runs, and confirm compatibility before ordering.