2Bros Parts

PISTON KIT 86-88 YZ125 57.25, WOSSNER 8118D125 YAMAHA MX

$139.12

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Delivery to United States 5–8 business days

Out of Stock

Wossner 57.25mm forged piston kit. This piston is manufactured in Germany and features an elliptical design for consistent bearing surface under heat expansion, reduced localised stress, and even distribution of thrust loads. It also supports efficient thermal management by optimising combustion chamber heat transfer to the cylinder walls. Bore 57.25mm, actual diameter 57.19mm, displacement 123 cm³, stroke 50.00mm, clearance 0.06mm, compression height 30.00mm, compression ratio 2-stroke. Includes lock CW16, pin WP036, and ring set RSB5725. Wossner Piston Kit No.: 8118D125.

Specifications
SKU
56-W559+125.WO
Brand
Wossner
Availability
Out of Stock
General Product Group
Engine
General Product Type
Pistons & Kits
General Size
57.25mm
Variant Id
256823
Delivery5–8 business days
14-Day ReturnsHassle-free
Easy CheckoutCard friendly
Product details

FULL DESCRIPTION

Wossner 57.25mm Forged Piston Kit for Yamaha YZ125

Enhance the performance and durability of your Yamaha YZ125 with this Wossner 57.25mm (+1.25 oversize) forged piston kit. Engineered and manufactured in Germany, this high-quality piston is designed to withstand the demands of two-stroke motocross riding.

Key Features:

  • Forged Construction: Crafted using a forging process for superior strength and longevity.
  • Elliptical Design: Ensures a consistent bearing surface even under extreme heat expansion, reducing localized stress and distributing thrust loads evenly.
  • Optimized Thermal Management: Facilitates efficient heat transfer from the combustion chamber to the cylinder walls for reliable performance.
  • Reduced Stress and Wear: Prevents piston collapse by minimizing localized pressure and distributing thrust loads effectively.
  • German Engineering: Manufactured to exacting standards in Germany.

Specifications:

  • Bore: 57.25mm
  • Actual Diameter: 57.19mm
  • Displacement: 123 cm³
  • Stroke: 50.00mm
  • Clearance: 0.06mm
  • Compression Height: 30.00mm
  • Compression Ratio: 2-stroke

Included Components:

  • Piston Kit Part No.: 56-W559+
  • Wossner Piston Kit No.: 8118D125
  • Lock: CW16
  • Pin: WP036
  • Ring Set: RSB5725
Before you buy

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Yes. We ship from the UK. Orders ship within 3 working days, then delivery to the United States takes 5–8 business days. The delivery price is shown at checkout before you pay. Delivery details

Yes. You have 14 days from delivery to return it, unused and in its original packaging. Contact us first and we will send you the return instructions. Returns policy

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Out of stock