2Bros Parts

PISTON KIT 86-88 YZ125 57.50, WOSSNER 8118D150 YAMAHA MX

$139.93Only 1 left

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This Wossner 57.50mm (+1.50 oversize) forged piston kit is produced in Germany. The forged process enhances durability and strength. Its elliptical shape helps maintain a consistent bearing surface during thermal expansion, reducing localised stress and evenly distributing thrust loads to prevent piston collapse. The piston also supports efficient heat transfer from the combustion chamber to the cylinder walls, ensuring reliable performance in two-stroke engines. Features include forged piston for increased structural strength and durability, elliptical design for a uniform bearing surface during heat expansion, minimised localised pressure, even distribution of thrust loads, and support for efficient combustion heat transfer to cylinder walls. Specifications: Bore 57.50mm, actual diameter 57.44mm, displacement 123 cm³, stroke 50.00mm, clearance 0.06mm, compression height 30.00mm, compression ratio 2-stroke. Cross-reference OEM Part Numbers include Piston Kit Part No. 56-W559+150.WO, Wossner Piston Kit No. 8118D150, Lock CW16, Pin WP036, and Ring Set RSB5750.

Specifications
SKU
56-W559+150.WO
Brand
Wossner
Availability
In Stock (1)
General Product Group
Engine
General Product Type
Pistons & Kits
General Size
57.5mm
Variant Id
256824
Delivery5–8 business days
14-Day ReturnsHassle-free
Easy CheckoutCard friendly
Product details

FULL DESCRIPTION

Wossner 57.50mm Forged Piston Kit for Yamaha YZ125

Enhance the performance and durability of your Yamaha YZ125 with this premium Wossner forged piston kit. Precisely engineered in Germany, this 57.50mm (+1.50mm oversize) piston is designed to withstand the rigors of high-performance two-stroke engines.

Key Features:

  • Forged construction for superior strength and longevity.
  • Elliptical piston design ensures a consistent bearing surface during thermal expansion, reducing stress and evenly distributing thrust loads.
  • Promotes efficient heat transfer from the combustion chamber to the cylinder walls for optimal operating temperatures.
  • Precision manufactured in Germany for uncompromising quality.

Specifications:

  • Bore: 57.50mm
  • Actual Diameter: 57.44mm
  • Displacement: 123 cm³
  • Stroke: 50.00mm
  • Clearance: 0.06mm
  • Compression Height: 30.00mm
  • Compression Ratio: 2-stroke

Included Components:

  • Piston
  • Lock: CW16
  • Pin: WP036
  • Ring Set: RSB5750

Cross-Reference OEM Part Numbers:

  • Wossner Piston Kit No.: 8118D150
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