PISTON KIT 88-91 YZ250 69.50, WOSSNER 8134D150 YAMAHA MX

Wossner Forged Piston Kit 69.50mm Bore – Yamaha YZ250 / WR250 (1988–1991)
This Wossner forged piston kit is tailored for Yamaha YZ250 and WR250 models from 1988 to 1991. It features a 69.50 mm bore and a piston diameter of 69.44 mm (+1.50 mm oversize), making it suitable for engines requiring increased clearance or cylinder refinishing. Forged in Germany, the piston offers exceptional strength and thermal efficiency. The elliptical design ensures uniform bearing contact, improving reliability under thermal expansion and high load.

Features

• Forged piston construction enhances strength and longevity

• Optimised for efficient heat transfer to cylinder walls

• Elliptical design ensures even pressure distribution and reduces wear

• Made in Germany with high manufacturing precision

Specifications

• Bore Size: 69.50 mm

• Piston Diameter: 69.44 mm

• Engine Displacement: 246 cm³

• Stroke: 68.00 mm

• Clearance: 0.06 mm

• Compression Height: 36.00 mm

• Compression Ratio: 2-stroke (Wossner and OEM)

Cross-Reference Wossner Part Numbers

• Piston Kit: 8134D150

• Lock: CW18

• Pin: WP033

• Ring Set: RSB6950 x 2

Vehicle Fitments

• 1988 Yamaha YZ250

• 1988 Yamaha WR250

• 1989 Yamaha YZ250

• 1989 Yamaha WR250

• 1990 Yamaha YZ250

• 1990 Yamaha WR250

• 1991 Yamaha YZ250

• 1991 Yamaha WR250