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

Name: Athena 19-24 Yamaha YZ 85 53mm Bore 106cc Big Bore Cylinder Kit
Brand: Athena
SKU: A0EF P400485100077
Price: 834.75 USD
Availability: OutOfStock

$1,053.95 $834.75 Save $219.20

SKU: A0EF P400485100077

In Stock

Ships by Jun 15

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Non-Returnable Item

DIY PRO SHOP

Moderate — 2–4 hours

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

Brand	Athena
Part Number	A0EF P400485100077

Videos

What Is An Athena Big Bore Kit | YZ125 Build | What Comes In The Box

Performing case mods to big bore cylinders

Athena YZ144 Kit - Big Bore Case Mods and Top End Install. Project YZ144 part 6

NEW PRODUCT Athena Top End Piston Kit - 2T 4T 🆕

YAMAHA YZ 125 | ATHENA CYLINDER ASSEMBLY | RAW VIDEO

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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