PISTON KIT 98-01 YZ125 54.00 A, WOSSNER 8091DA YAMAHA MX 4XM-11631-30-A0

This Wossner piston kit with a 54.00mm bore is designed for Yamaha YZ125 and WR125 models from 1998 to 2001. Precision-forged in Germany, it delivers exceptional strength, heat dissipation, and reliability for two-stroke performance applications.

Features

• Forged piston construction provides high strength and durability

• Optimised for effective heat transfer from the combustion chamber to the cylinder wall

• Elliptical shape enhances load distribution and reduces risk of piston collapse under heat expansion

• Manufactured in Germany for precision and quality

Specifications

• Bore size: 54.00 mm

• Actual piston size: 53.95 mm

• Display (cm³): 125

• Stroke (mm): 54.50

• Clearance (mm): 0.05

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

• Dome volume: Not specified

• Compression height (mm): 28.00

• Theoretical weight: Not specified

Cross-Reference OEM Part Numbers

• 4XM-11631-30-A0

• 09104819

• 726M05400

Vehicle Fitments

• 1998 Yamaha WR125

• 1998 Yamaha YZ125 Base

• 1999 Yamaha WR125

• 1999 Yamaha YZ125 Base

• 2000 Yamaha WR125

• 2000 Yamaha YZ125 Base

• 2001 Yamaha WR125

• 2001 Yamaha YZ125 Base

Included Components

• Piston: Wossner PN# 8091DA

• Lock: PN# CW15

• Pin: PN# WP032

• Ring Set: PN# RSB5400

• Rod: PN# P2019