Yamaha YZF-R6 Piston Kit - Wiseco - 25787XA, 65.50 mm Bore, 13.5:1 CR - `01-`05. This Wiseco Forged Series piston kit is built for R6 models from 2001–2005 and provides a complete replacement piston package designed for high-stress street and track use.

Designed specifically for the Yamaha YZF-R6 01–05 platform, this kit includes a forged piston with a 65.50 mm bore and a 13.5:1 compression ratio. The forged construction offers improved strength and service life over cast pistons, and the kit ships complete with the wrist pin, piston rings, and circlips needed for installation. This makes the kit a direct way to restore top-end reliability or to prepare an engine for higher-performance tuning while keeping fitment and geometry consistent with OEM dimensions.

Features

• Wiseco forged piston, part number 25787XA, 65.50 mm bore
• 13.5:1 compression ratio matched to R6 2001–2005 applications
• Complete kit includes piston, wrist pin, rings, and circlips
• Forged construction for increased durability under high stress

If you have questions or need advice on fitment, call us directly — we’re happy to help. We offer installation and customization services at two locations: Austin, Texas and the Los Angeles, California area. Call 512-982-9393 (TX) or 562-981-6800 (CA) to book service or ask questions. If you’re considering 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