PISTON KIT 08-13 YFM250R 74.00, WOSSNER 8724DA YAMAHA ATV, 1S4-11631-20-A0

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

Dispatch Times

Local Stock: Dispatches in < 24 hours

Parts showing as available at our Warehouse in Gorey ship the same business day if ordered before 1pm. 

Supplier Stock: Dispatches in 2-4 Days

Parts showing as available at our Supplier Warehouse are ordered from our supplier and delivered to us before we can dispatch. More info is available on this page under "Stock Availability".

OEM Special Order: Dispatches in 3-10 Days

This website does not have access to live stock levels from our OEM Suppliers. In most cases the parts will be available but in the case of backordered parts we will notify you. We receive parts from Yamaha in 3-4 days, All others including Honda, Suzuki, Kawasaki, Polaris please allow 7-10 days for us to receive the parts. 

Delivery Times

Ireland & Northern Ireland:

1-2 Days using GLS/An Post

Germany, France, Netherlands, Belgium:

3-5 Days using GLS/Fedex

Italy, Spain & Other EU Countries:

4-7 Days using GLS/Fedex