PISTON KIT 86-88 YZ125 57.25, WOSSNER 8118D125 YAMAHA MX
4.1 Trustpilot 99.9% positive on eBay
Free UK delivery 2–4 business days
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.
- 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
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
QUESTIONS? JUST ASK
Talk to John or Phil. Real people, Monday to Friday, 10:00 to 17:00.
Call or email us with your make, model and year and we will check it for you before you order.
UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. 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
By card, PayPal, Apple Pay or Google Pay, or spread the cost with Klarna. Payment is taken securely by Stripe, and the options for your order are shown at checkout.
More answers in our FAQ.
Trade pricing available
Buying parts for your business? Apply for a 2BrosParts trade account.