Exterior Components› Body Panels and Components
Athena
Athena 19-23 Yamaha YZ 250 F 77mm Bore 250cc Standard Bore Gasket Kit
SKU: A0EF P400485160072
Advanced — 4+ hours
Description
Part #: P400485160072
The Standard Bore cylinder kit developed by Athena guarantees the same performance as the original spare parts, extreme reliability and optimal smoothness as a result of the lightweight aluminum cylinder, the barrel with nickel-silicon coating, and a piston designed to reduce further friction. The kit includes the high-quality aluminum cylinder with standard bore, the complete piston with the piston pin and rings, and all the necessary gaskets.
Fitment
Fitment Guaranteed
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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.
Available on iOS & Android
Specifications
| Brand | Athena |
| Part Number | A0EF P400485160072 |
Videos
Part 1: Installing Athena 290 Big Bore Kit- Yamaha WR/ YZ 250
Top End Piston Kit: all you need in one kit! 🔥
Athena 4-Stroke Cylinder Kit Review by MotoEverything
Athena YZ144 Kit - Big Bore Case Mods and Top End Install. Project YZ144 part 6
Complete Guide to Installing the Athena Big Bore Cylinder Kit - Step-by-Step Tutorial
Part 4: Installing Athena 290 Big Bore Kit- Yamaha WR/ YZ 250
Time for overhaul your dirt bike? Athena Top End Piston Kit 🔧
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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