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Engines and Components Cylinder Heads and Components

Athena

Athena 19-24 Yamaha YZ 85 53mm Bore 106cc Big Bore Cylinder Kit

$1,053.95 $834.75 Save $219.20

SKU: A0EF P400485100077

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In Stock
Ships by Aug 5
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

Part #: P400485100077

Athena has been constantly investing in cylinder aftermarket replacement parts for more than ten years, to improve their production and performance. All the cylinders are entirely engineered in Italy by Athena's R&D Department which has a strong internal know-how and cutting-edge tools to design and test each piece. They are coated with motor-nicksil, a nickel-silicon coating developed by Athena to obtain smoothness and optimal wear resistance.

MIA's Description

Kits include aluminum cylinder with nickel-carbide coating designed with larger water jackets. Includes forged piston, rings, clips, and pin. Athena top-end gasket set includes required seals and hardware. Easy-to-follow step-by-step installation instructions. Most are bolt-on; no machining required except where noted. This kit converts the stock 47.5mm bore Yamaha YZ 85 to a 55mm big bore, increasing displacement. Intended for competition use.

Fitment

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Specifications

BrandAthena
Part NumberA0EF P400485100077

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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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