Yamaha YFM350 Warrior Piston Kit - Wiseco - 121 CR - `87-`13. A complete forged piston kit specifically for the Yamaha YFM350 Warrior/Raptor models from 1987–2013, supplied in a 121 CR configuration with an 83.00 mm bore and 12:1 compression ratio.

This Wiseco piston kit is built for riders who want a reliable, application-specific replacement or upgrade. Wiseco’s forged 4-stroke pistons are manufactured to tight tolerances and machined for the YFM350 platform to provide consistent fit and durability. The kit includes high-quality piston rings, wrist pin(s), and circlips, and uses dedicated forgings to optimize strength-to-weight characteristics. Engineered and machined in Mentor, Ohio, the components are suited for owners performing maintenance, rebuilding, or light performance customization.

Features

• Forged 4-stroke Wiseco piston engineered for Yamaha YFM350 Warrior/Raptor (`87–`13)
• 83.00 mm bore, 12:1 compression ratio (Std Bore: 83 mm)
• Includes piston rings, wrist pin(s), and circlips
• Dedicated forging for improved strength-to-weight characteristics
• Engineered, forged, and machined in the USA (Mentor, OH)

This kit is a straightforward choice for enthusiasts who need a factory-fit replacement or want a durable piston for custom engine work without unnecessary speculation about gains. If you have questions about fitment, piston selection, or installation options, please call us directly — we can help confirm compatibility for your specific build.

We have two service locations offering installation and customization: Austin, Texas and the Los Angeles, California area. Call us at 512-982-9393 (TX) or 562-981-6800 (CA) with any questions or to schedule service. If you’re thinking about purchasing multiple items, contact us for possible shipping discounts. We install on premises at both locations.

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