Engines and Components› Pistons and Piston Rings
Athena
Athena 97-21 Yamaha YZ 125 53.94mm 2T Cast Piston
SKU: A0EF S4C05400016A
Beginner — under 30 min
Description
Part #: S4C05400016A
Athena, leader in producing motorcycle spare parts for over 40 years, unveils its new range of 4-stroke off-road cast pistons. Produced with cutting-edge CNC machining tools, which ensure dimensional tolerances of less than 0.01 mm, Athena pistons are made of special high-performance materials (nickel, silica, and aluminum alloys) that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance. The perfectly smooth profile ensures a regular flow and the perfect flame propagation. Some pistons' skirts are moreover treated with a molybdenum disulfide coating applied by screen printing which further reduce friction to enhance performance and durability.
MIA's Description
This cast piston features a flat top and a standard size A designation, with a bore size of 53.94mm. It is constructed from 4032 aluminum alloy with a high silicon content for durability and heat resistance, and has a compression ratio of 14.8:1.
Fitment
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Specifications
| Brand | Athena |
| Part Number | A0EF S4C05400016A |
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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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