PISTON KIT 1997 YZ125 54.00, WOSSNER 8117DC YAMAHA MX

This Wossner forged piston kit is engineered for the 1997 Yamaha YZ125 and features a 54.02mm bore (+0.02mm oversize). Made in Germany, the piston is designed with an elliptical profile that accommodates thermal expansion by providing an even bearing surface. This reduces localised stress, distributes thrust loads uniformly, and prevents piston collapse. It also enables effective heat transfer from the combustion chamber to the cylinder wall, supporting engine reliability in demanding conditions.

Features

• Forged piston for maximum strength and durability

• Elliptical design ensures uniform pressure distribution under heat

• Reduces risk of structural failure due to piston collapse

• Supports consistent combustion heat transfer

• German-engineered for precision and performance

Specifications

• Bore Size: 54.02mm (+0.02mm oversize)

• Actual Diameter: 53.96mm

• Compression Height: 28.00mm

• Stroke: 54.50mm

• Displacement: 124 cm³

• Piston Clearance: 0.06mm

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

Cross-Reference OEM Part Numbers

• Wossner Piston Kit Part No: 8117DC

• Lock: CW15

• Pin: WP032

• Ring Set: RSB5400

• Rod: P2019

Vehicle Fitments

• 1997 Yamaha YZ125