Yamaha YFM350 Piston Kit - Wiseco - 10.251 - `87-`13. This Wiseco piston kit is designed for Yamaha YFM350 Warrior/Raptor models from 1987–2013 and provides a direct-fit forged piston solution for riders who want durable, engine-specific components.

Wiseco's forged 4-stroke pistons are engineered and machined in the USA to tight tolerances for consistent performance and long service life. This kit is a +1 overbore with an 84.00 mm bore and a 10.25:1 compression ratio, built from dedicated forgings that balance strength and weight for this specific engine family. The kit includes high-quality piston rings, wrist pin(s), and circlips, allowing a straightforward installation or overhaul when paired with proper machine work and measurements.

Features

• Forged 4-stroke piston engineered for the Yamaha YFM350 Warrior/Raptor (`87–`13)
• +1 overbore — Bore: 84.00 mm; Compression Ratio: 10.25:1
• Includes piston rings, wrist pin(s), and circlips
• Dedicated forging for optimized strength-to-weight characteristics
• Manufactured and machined in Mentor, Ohio, USA

This Wiseco kit is a practical choice for enthusiasts rebuilding or customizing a YFM350 who want a durable, application-specific piston without unnecessary guesswork. If you have any questions about fitment, clearances, or compatibility with your build, please call us directly — we’re happy to help. We have two locations offering installation and customization services: Austin, Texas and the Los Angeles, California area. Call: 512-982-9393 (TX) or 562-981-6800 (CA).

If you are thinking about purchasing multiple items, contact us for shipping discounts. We install on premises at both locations.

CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov