4675M07150 Wiseco Piston Kit for Yamaha Timberwolf 250 1990-2000 .020 71.50

Wiseco .020 Piston Kit for Yamaha Timberwolf 250

This .020 oversize piston kit for Yamaha Timberwolf 250 is a rebuild component that restores compression and bore fit to the 250cc single, referencing OEM cross-reference 4675M07150 with a 71.50mm bore and 8.7:1 compression ratio.

Overview

This Wiseco .020 piston kit serves riders rebuilding a worn or scored Yamaha Timberwolf 250 top end. The 71.50mm oversize bore and 8.7:1 compression ratio restore factory-style compression for the 1990-2000 model run. It suits DIY mechanics and shops handling a complete top-end refresh on this machine.

Built For Performance

• .020 oversize 71.50mm bore piston for use after cylinder boring
• 8.7:1 compression ratio matched to the 250cc Timberwolf powerplant
• Forged piston construction for strength under heat and load
• Kit includes piston, rings, wrist pin, and circlips for a complete install
• Cross-references OEM number 4675M07150 for easy lookup

Fits These Machines

• for Yamaha Timberwolf 250, 1990-2000

On-The-Job Use

• Top-end rebuild after cylinder scoring or piston wear
• Restoring compression on high-hours utility quads
• Shop or home garage engine refresh
• Bore-out rebuild matched to a .020 over cylinder

Specs At A Glance

Good To Know

Q: Does this piston drop into a stock cylinder? A: No, a .020 oversize piston requires the cylinder to be bored and honed to match the 71.50mm size before assembly.

Q: Can I install this without checking ring end gap? A: Ring end gap should always be measured and adjusted to spec during assembly to avoid poor sealing or seizure.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.