PISTON KIT 98-01 YZ125 54.00 A, WOSSNER 8091DA YAMAHA MX 4XM-11631-30-A0
4.1 Trustpilot 99.9% positive on eBay
Free UK delivery 2–4 business days
Spread the cost with 
18+, T&Cs apply
Wossner piston kit with a 54.00mm bore designed for Yamaha YZ125 and WR125 models from 1998 to 2001. Features forged piston construction for high strength and durability, optimized heat transfer, and an elliptical shape for enhanced load distribution. Manufactured in Germany. Specifications include a 54.00 mm bore size, 53.95 mm actual piston size, 125 cm³ displacement, 54.50 mm stroke, 0.05 mm clearance, 2-stroke compression ratio, 28.00 mm compression height. Cross-reference OEM part numbers: 4XM-11631-30-A0, 09104819, 726M05400. Included components: Piston (Wossner PN# 8091DA), Lock (PN# CW15), Pin (PN# WP032), Ring Set (PN# RSB5400), Rod (PN# P2019). Weight: 182g.
- SKU
- 56-W726.A.WO
- Brand
- Wossner
- Availability
- In Stock (1)
Fitments (12)
| Make | Model | Year |
|---|---|---|
| GAS-GAS | MC 125 | 2000 |
| GAS-GAS | MC 125 | 2001 |
| GAS-GAS | MX 125 | 2000 |
| GAS-GAS | MX 125 | 2001 |
| GASGAS | EC 125 | 2000 |
| GASGAS | EC 125 | 2001 |
| YAMAHA | YZ 125 | 1996 |
| YAMAHA | YZ 125 | 1997 |
| YAMAHA | YZ 125 | 1998 |
| YAMAHA | YZ 125 | 1999 |
| YAMAHA | YZ 125 | 2000 |
| YAMAHA | YZ 125 | 2001 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 54.00mm
- Variant Id
- 257552
FULL DESCRIPTION
Wossner Piston Kit 54.00mm Bore for Yamaha YZ125 / WR125 (1998-2001)
Enhance your motorcycle's performance with this precision-engineered Wossner Piston Kit. Designed for durability and power, this kit features a forged piston constructed in Germany, ensuring exceptional strength and reliability for demanding two-stroke applications.
Key Features:
- Forged piston construction for superior strength and longevity.
- Optimized for efficient heat transfer from the combustion chamber to the cylinder wall, promoting consistent performance.
- Elliptical piston shape designed to improve load distribution and mitigate risks of piston collapse due to heat expansion.
- Manufactured to exacting standards in Germany, guaranteeing high-quality craftsmanship.
Specifications:
- Bore Size: 54.00 mm
- Actual Piston Size: 53.95 mm
- Displacement (cm³): 125
- Stroke (mm): 54.50
- Clearance (mm): 0.05
- Compression Ratio: 2-stroke (Wossner and OEM compatible)
- Compression Height (mm): 28.00
Cross-Reference OEM Part Numbers:
- 4XM-11631-30-A0
- 09104819
- 726M05400
Included Components:
- Piston: Wossner PN# 8091DA
- Lock: PN# CW15
- Pin: PN# WP032
- Ring Set: PN# RSB5400
- Rod: PN# P2019
QUESTIONS? JUST ASK
Talk to John or Phil. Real people, Monday to Friday, 10:00 to 17:00.
Check the fitment table on this page against your make, model and year. Not sure? Call or email us 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.