PISTON KIT 1989 YZ125 56.50, WOSSNER 8131D050 YAMAHA MX

Wossner Forged Piston Kit 56.50mm Bore – Yamaha YZ125 1989 (8131D050 +0.50)
This Wossner forged piston kit with a +0.50mm oversize bore (actual 56.44mm) is developed for the 1989 Yamaha YZ125. Designed for high-performance 2-stroke engines, the forged piston offers superior strength and heat transfer capabilities. The elliptical shape ensures balanced load distribution during thermal expansion, effectively minimising localised pressure and reducing the risk of structural failure. Made in Germany for consistent precision and performance.

Features

• High-strength forged aluminium piston for demanding 2-stroke use

• Enhanced heat transfer from combustion chamber to cylinder walls

• Elliptical design ensures uniform bearing surface under expansion

• Suitable for 2-stroke engine performance requirements

• Precision engineered in Germany

Specifications

• Bore Size: 56.50mm (+0.50 oversize)

• Actual Bore: 56.44mm

• Compression Height: 28.00mm

• Clearance: 0.06mm

• Stroke: 50.00mm

• Displacement: 123 cm³

• Wossner Compression Ratio: 2-stroke

• OEM Compression Ratio: 2-stroke

Cross-Reference OEM Part Numbers

• Wossner Piston: 8131D050

• Ring Set: RSB5650

• Lock: CW16

• Pin: WP036

• Rod: P2047

• Internal Reference: 56-W582+050.WO

Vehicle Fitments

• 1989 Yamaha YZ125