PX2222B PISTON KIT ALUMINUM 53.95MM B

Name: PROX PISTON KIT ALUMINUM 53.95MM B
Brand: PROX
SKU: PX2222B
Price: 98.73 GBP
Availability: InStock

Fits Yamaha YZ 125

RRP £123.41 Save 20%

£98.73

incl. VAT

In stock — ships in 3 working days

Usually dispatched within 3 working days.

Part #: PX2222B

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§ 02 / About this part

What it is

The PROX PISTON KIT ALUMINUM 53.95MM B, motocross part. Stocked by Iron Offroad, the UK MX hard parts specialist.

This piston kit is a direct replacement for OEM part 5NY-11631-01-A0. It sits in the top-end of your engine and handles the combustion forces. The B-size accounts for minor bore wear in used cylinders. Regular replacement is essential for 2-stroke performance and prevents catastrophic engine failure. This kit comes complete with rings, pin, and clips for a full refresh. Check your ring gap during the install to ensure long-term reliability. It provides a reliable seal for consistent compression on every stroke. Ensure the cylinder is measured before fitting.

§ 03 / Specs

The numbers

Brand: PROX
Part number: PX2222B
Weight: 0.18 kg
OEM cross-refs: 5NY-11631-01-A0
VAT: 20%

// Fitment

Will it fit your bike?

Fits 1 model · 1 year-band

Yamaha YZ 125 2002–2004

* 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.