Athena 58mm Complete 144cc Big Bore Motor Rebuild Kit! This is the best and most reliable rebuild kit on the market! Fits Yamaha YZ125 2 Stroke Dirt Bikes. 58mm 144cc Nikasil Athena Big Bore Cylinder.
Athena 58mm Coated Piston Kit (Includes, Piston, Pin, Rings & Clips). Hotrods Heavy Duty Crank Shaft. Hotrods Heavy Duty Main Bearings. Bottom End Oil Seals Kit.
This is a bolt on kit.