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Engines and Components› Pistons and Piston Rings

Athena

Athena 97-21 Yamaha YZ 125 57.94mm Bore 2T Cast Piston

$268.95 $209.25 Save $59.70

SKU: A0EF S4C05800001A

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In Stock
Ships by Jun 12
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Athena S4C05800001A is a 144cc big bore cast piston kit for Yamaha YZ125 (2005-2021) and YZ125X (2020-2022) motorcycles, designed to enhance performance and withstand mechanical and thermal stresses.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

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

BrandAthena
Part NumberA0EF S4C05800001A

Videos

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

What Is An Athena Big Bore Kit | YZ125 Build | What Comes In The Box
Athena YZ144 Kit - Big Bore Case Mods and Top End Install. Project YZ144 part 6

Athena YZ144 Kit - Big Bore Case Mods and Top End Install. Project YZ144 part 6
YAMAHA YZ 125 | ATHENA CYLINDER ASSEMBLY | RAW VIDEO

YAMAHA YZ 125 | ATHENA CYLINDER ASSEMBLY | RAW VIDEO
2001 YZ 125 Big Bore kit (134) First time start up - YAMAHA - Walk around

2001 YZ 125 Big Bore kit (134) First time start up - YAMAHA - Walk around

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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