PISTON KIT 99-25 YZ250 66.40 A, PROX 01.2321.A RM250 03-12
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ProX piston kit with 66.40mm bore. This kit features a low-expansion, low-friction piston alloy, the same used by major Japanese engine manufacturers. ProX pistons are precision machined on CNC equipment. This piston kit is a first-class replacement for the original piston in your Motorcycle, Scooter, Moped, ATV, or Personal Watercraft. Coated for ultimate performance, the OEM style Tin coating assists the wear-in process, and a new skirt coating reduces friction after wear-in, increasing performance. Includes piston size: 66.35mm. Manufacturer part number: 01.2321.A. Weight: 296g.
- SKU
- 56-W742.A.PX
- Brand
- Pro-X Racing
- Availability
- In Stock (2)
Fitments (51)
| Make | Model | Year |
|---|---|---|
| FANTIC | XX 250 | 2022 |
| FANTIC | XX 250 | 2023 |
| FANTIC | XX 250 | 2024 |
| FANTIC | XX 250 | 2025 |
| SUZUKI | RM 250 | 2003 |
| SUZUKI | RM 250 | 2004 |
| SUZUKI | RM 250 | 2005 |
| SUZUKI | RM 250 | 2006 |
| SUZUKI | RM 250 | 2007 |
| SUZUKI | RM 250 | 2008 |
| SUZUKI | RM 250 | 2009 |
| SUZUKI | RM 250 | 2010 |
| SUZUKI | RM 250 | 2011 |
| SUZUKI | RM 250 | 2012 |
| YAMAHA | YZ 250 | 1999 |
| YAMAHA | YZ 250 | 2000 |
| YAMAHA | YZ 250 | 2001 |
| YAMAHA | YZ 250 | 2002 |
| YAMAHA | YZ 250 | 2003 |
| YAMAHA | YZ 250 | 2004 |
| YAMAHA | YZ 250 | 2005 |
| YAMAHA | YZ 250 | 2006 |
| YAMAHA | YZ 250 | 2007 |
| YAMAHA | YZ 250 | 2008 |
| YAMAHA | YZ 250 | 2009 |
| YAMAHA | YZ 250 | 2010 |
| YAMAHA | YZ 250 | 2011 |
| YAMAHA | YZ 250 | 2012 |
| YAMAHA | YZ 250 | 2013 |
| YAMAHA | YZ 250 | 2014 |
| YAMAHA | YZ 250 | 2015 |
| YAMAHA | YZ 250 | 2016 |
| YAMAHA | YZ 250 | 2017 |
| YAMAHA | YZ 250 | 2018 |
| YAMAHA | YZ 250 | 2019 |
| YAMAHA | YZ 250 | 2020 |
| YAMAHA | YZ 250 | 2021 |
| YAMAHA | YZ 250 | 2022 |
| YAMAHA | YZ 250 | 2023 |
| YAMAHA | YZ 250 | 2024 |
| YAMAHA | YZ 250 | 2025 |
| YAMAHA | YZ 250X | 2016 |
| YAMAHA | YZ 250X | 2017 |
| YAMAHA | YZ 250X | 2018 |
| YAMAHA | YZ 250X | 2019 |
| YAMAHA | YZ 250X | 2020 |
| YAMAHA | YZ 250X | 2021 |
| YAMAHA | YZ 250X | 2022 |
| YAMAHA | YZ 250X | 2023 |
| YAMAHA | YZ 250X | 2024 |
| YAMAHA | YZ 250X | 2025 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 66.40mm
- Variant Id
- 257589
FULL DESCRIPTION
ProX Piston Kit 66.40mm Bore
This ProX Piston Kit is engineered for optimal performance and durability. Featuring a 66.40mm bore and a 66.35mm piston size, this kit is crafted using state-of-the-art CNC equipment. The alloy used is the same low-expansion, low-friction material favored by major Japanese engine manufacturers, ensuring a high-quality replacement for your original piston.
Key Features:
- Precision machined using advanced CNC equipment.
- Utilizes a low-expansion, low-friction piston alloy.
- Designed as a premium replacement for original pistons.
- Includes advanced skirt coating to aid the initial wear-in process and reduce friction.
- Coating is a proprietary blend designed to enhance performance.
This ProX piston kit offers a first-class solution for various powersports applications, enhancing both the break-in period and long-term running efficiency of your engine.
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Check the fitment table on this page against your make, model and year. Not sure? Call or email us and we will check it for you before you order.
UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details
Yes. You have 14 days from delivery to return it, unused and in its original packaging. Contact us first and we will send you the return instructions. Returns policy
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