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2Bros MCS LTD Company number 16176735 - Vat No. GB 508324506 - info@2bros-mx.com - Tel: 03301333748
This Wossner 57.00mm (+1.00 oversize) forged piston kit is specifically engineered for Yamaha YZ125 two-stroke models from 1986 to 1988. Made in Germany, it features a high-strength forged construction with an elliptical design that enhances structural integrity, promotes even distribution of combustion forces, and improves thermal management. Its design ensures consistent and reliable performance under demanding riding conditions.
Features
Forged piston for high strength and durability
Elliptical design provides uniform bearing surface during heat expansion
Even thrust load distribution helps prevent localised stress and piston collapse
Designed for effective combustion heat transfer to the cylinder walls
Manufactured in Germany
Specifications
Bore: 57.00mm
Actual diameter: 56.94mm
Displacement: 123 cm³
Stroke: 50.00mm
Clearance: 0.06mm
Compression height: 30.00mm
Compression ratio: 2-stroke
Cross-Reference OEM Part Numbers
Piston Kit Part No.: 56-W559+100.WO
Wossner Piston Kit No.: 8118D100
Lock: CW16
Pin: WP036
Ring Set: RSB5700
Vehicle Fitments
Yamaha YZ125 1986
Yamaha YZ125 1987
Yamaha YZ125 1988