Athena Forged Piston Kit 09100641 Ø66.34 mm for Yamaha YZ250 1999–2027 YZ250X 2016–2027

Name: Athena Forged Piston Kit 09100641 Ø66.34 mm for Yamaha YZ250 1999–2027 YZ250X 2016–2027
Brand: ATHENA
SKU: 09100641
Price: 115.8 GBP
Availability: InStock

Fits 2 bikes

RRP £139.52 Save 17%

£115.80

incl. VAT

In stock — delivered in 6–10 working days

Dispatched in 2–3 working days · delivered in 6–10.

Part #: 09100641

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§ 02 / About this part

What it is

Athena forged piston kit Ø66.34 mm to fit Yamaha YZ250 (1999–2027); Yamaha YZ250X (2016–2027).

This forged piston kit sits in the top-end of your 250cc 2-stroke. The 66.34mm diameter is a standard fitment for maintaining factory-spec clearances. Forged construction provides the structural strength needed for high-load racing and hard enduro use. Replacing the piston at regular intervals prevents skirt fatigue and potential cylinder damage. The kit includes the piston, rings, gudgeon pin, and circlips. Ensure the arrow on the crown faces the exhaust port during installation. Check your ring end-gap to ensure reliable operation under high thermal stress.

§ 03 / Specs

The numbers

Brand: ATHENA
Part number: 09100641
Category: Top End
Weight: 0.38 kg
VAT: 20%

// Fitment

Will it fit your bike?

Fits 2 models · 2 year-bands

* Fitment data is provided as a guide. Verify compatibility against the bike's owner's manual or service handbook before ordering. Iron Offroad accepts no liability for incorrect application. Full terms and conditions apply.

§ 05 / About Iron Offroad

Iron Offroad

Iron Offroad is the off-road sibling of Iron City and Iron Stable — a UK shop for motocross, enduro, and trail-bike hard parts. Every fitment lives on the site, listed against KTM, Husqvarna, GasGas, Yamaha, Honda, Kawasaki, Suzuki, and Beta. Pick your bike on the timing-tower. Our USP is the data: fully enriched fitment so you find the right part for your bike quickly and get it fitted accurately. Brands you'd find on a paddock workbench — pads, sprockets, plastics, fork seals, cables, gaskets, bars, the things that actually wear out. Road-bike kit, scooter parts, and quad gear sit elsewhere; dirt and e-moto only. We operate from our storage facility in Leeds. Iron Offroad is a trading name of Iron Stable Ltd, registered in Mildenhall — Company No. 17061294. The business has a rich motorcycle history across multiple moto brands — the photos show where we came from — and recently pivoted into hard parts and online retail.