Yamaha YZF-R1 Piston Kit - Wiseco - 74.00 mm Bore, 13:1 CR - `99-`03. A forged Wiseco piston kit engineered for 4-stroke Yamaha applications, supplied with the hardware needed for installation on compatible models.

This Forged Series kit is built for strength and service life, intended for riders and builders who demand reliable, track-capable components. The kit comes complete with piston, wrist pin, rings and circlips so you have everything required for a proper rebuild. Wiseco's forged construction is chosen for its durability under high-stress conditions, and the kit's 74.00 mm bore and 13:1 compression ratio match factory-replacement and performance-focused applications for the specified model years. It is suitable for YZF-R1 1999–2003 and is also listed for some FZ1 2001–2005 applications.

Features

• Forged piston construction for improved strength and longevity
• Complete kit: piston, wrist pin, rings, and circlips included
• Specifications: 74.00 mm bore, 13:1 compression ratio
• Designed for 4-stroke Yamaha YZF-R1 (`99–`03) and compatible FZ1 years
• Performance-focused geometry and material selection to support durability and power delivery

If you have questions or need help confirming fitment, call us directly — we’re happy to assist. We offer installation and customization services at two locations: Austin, Texas and the Los Angeles, California area. Call our Austin shop at 512-982-9393 (TX) or our California shop at 562-981-6800 (CA). If you are considering purchasing multiple items, contact us for potential shipping discounts. We install on premises at both locations.

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