Upgrade your YZ125 into a 144cc powerhouse with the best-performing and most reliable big bore kit on the market. This Athena kit includes everything you need for a full top-end rebuild—engineered for more power and factory-level reliability.
Athena 58mm Nikasil Big Bore Cylinder (144cc)
Athena Coated Piston Kit (Piston, rings, wrist pin, and circlips)
Athena Complete Top End Gasket Set
Athena Cylinder Head
Athena Head Stud Kit
Athena Power Valves
All components are brand new and covered by Athena’s warranty.
Fits Yamaha YZ125 (2-stroke) models:
1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
Manufacturer warranty included
Installation by a qualified technician is required
Warranty does not cover misuse, improper tuning, or incorrect break-in procedures
We ship next day most of the time. Modquad parts are shipped Monday-Thursday. Engine Kits are 3-5 business days.
We don't do backorder! If your items has already sold you will be notified immediately and you money refunded on the spot.
Sold items are removed daily.
If you see it on this website, it is 100% in stock unless it just sold before you clicked buy.
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