WOSSNER 74mm PISTON KIT YAMAHA YFM250R RAPTOR 08-13, XT250 13-18

The Wossner 8724DA forged piston kit with a 74.00mm bore is designed for Yamaha YFM250R Raptor (2008–2013) and YBR250 (2008–2012). Manufactured in Germany, this high-compression piston enhances strength and heat transfer performance. Its elliptical shape ensures even pressure distribution during thermal expansion, reducing the risk of piston failure.

Features

• Forged high-compression piston for durability and performance
• Engineered for efficient heat transfer to cylinder walls
• Elliptical design ensures uniform pressure distribution during heat expansion
• Reduces localized stress and risk of piston collapse
• Manufactured in Germany

Specifications

• Bore: 74.00 mm
• Actual Bore Diameter: 73.95 mm
• Hub Stroke: 58.00 mm
• Clearance: 0.05 mm
• Compression Height: 23.50 mm
• Dome Volume: +2.40 cm³
• Wossner Compression Ratio: 12.00:1
• OEM Compression Ratio: 9.50:1

Cross-Reference OEM Part Numbers

• Piston: 8724DA
• Lock: CW17
• Pin: WP083
• Ring Set: 740XDS
• Part No.: 56-W4950.A.WO
• OEM Reference: 1S4-11631-20-A0, 40078M07400

Vehicle Fitments

• Yamaha YFM250R Raptor 2008–2013
• Yamaha YBR250 2008–2012