NAMURA FX-40037K Top End Repair Kit 76.96MM YZ250F/YZ250FX/WR250F

( Brand: Namura ), ( Manufacturer Part Number: FX-40037K )

Review NAMURA Top End Repair Kit 76.96mm Size #fx-40037k Yamaha Yz250f/yz250fx/wr250f fits YZ250F YZ250FX WR250F

The Namura FX-40037K Top End Repair Kit is specifically designed for Yamaha YZ250F, YZ250X, and WR250F motorcycles with a 76.96mm bore size. This comprehensive repair kit includes all the necessary components to overhaul the top end of your engine, ensuring optimal performance and longevity.

The heart of this repair kit are the high-quality, precision-machined piston and piston ring set. The piston is made from a forged aluminum alloy, offering superior strength and durability. The piston rings are designed to provide an excellent seal and minimize compression loss. Both components are treated with a special coating for enhanced wear resistance and reduced friction.

The kit also includes a set of new, high-performance cylinder liners. These liners are precision-machined from high-tensile aluminum alloy and feature a unique JIS Nitriding process that significantly enhances their durability and reduces the risk of scuffing. This results in a smoother, more efficient combustion process and improved engine power.

Additionally, the Namura FX-40037K Top End Repair Kit comes with a matching set of new, high-performance piston pins and piston pin bushings. These components are made from high-strength materials and feature a precision-machined finish for a perfect fit and maximum durability.

The kit also includes a set of new, high-performance connecting rods and rod bearings. These components are designed to provide superior strength and durability, ensuring the engine runs smoothly and efficiently. The rod bearings feature a high-quality, low-friction material for reduced wear and longer service life.

Lastly, the Namura FX-40037K Top End Repair Kit includes a set of new, high-quality gaskets and seals to ensure a proper seal between all engine components. These gaskets are made from a high-quality, heat-resistant material that can withstand the extreme temperatures and pressures found in a motorcycle engine.

In summary, the Namura FX-40037K Top End Repair Kit is a complete solution for overhauling the top end of your Yamaha YZ250F, YZ250X, or WR250F motorcycle engine. With high-quality, precision-machined components designed for superior performance and durability, this kit is an essential tool for any serious motorcycle enthusiast or racer.

The Namura FX-40037K top end repair kit is designed specifically for Yamaha YZ250F, YZ250X, and WR250F motorcycles with a 76.96mm bore size. This repair kit includes various parts needed for a top end rebuild, such as piston, piston rings, cylinder liner, and gaskets. Here are some pros and cons of buying this repair kit:

1. Designed for Yamaha motorcycles: The kit is specifically made for Yamaha YZ250F, YZ250X, and WR250F models, ensuring a perfect fit.

2. Includes various parts: The kit contains many necessary parts for a top end rebuild, reducing the need to purchase individual components.

3. High-quality materials: Namura is known for producing high-quality motorcycle parts, including their repair kits.

4. Can save money: Performing the top end rebuild yourself with this kit can save significant money compared to taking it to a professional shop.

5. Improved performance: A fresh top end can lead to improved engine performance and efficiency.

1. Requires time and effort: Top end rebuilds can take a considerable amount of time and effort to complete, especially for those without experience.

2. Risk of damaging parts: Improper installation or handling of parts during the rebuild process could result in damage, requiring additional repairs or replacement parts.

3. Potential for additional costs: If any unexpected damages or issues arise during the rebuild process, additional costs might be incurred.

4. Skills and tools required: A successful rebuild requires a good understanding of engine mechanics and access to necessary tools.

In conclusion, the Namura FX-40037K top end repair kit offers several benefits for Yamaha YZ250F, YZ250X, and WR250F motorcycle owners, including a perfect fit, a comprehensive set of parts, and potential cost savings. However, it also comes with challenges such as the time and effort required, the risk of damaging parts, and the need for skills and tools. Ultimately, whether or not to purchase this repair kit depends on one's experience level, availability of time, and willingness to take on the project.

If you're confident in your abilities and willing to invest the time, the Namura FX-40037K top end repair kit could be a smart investment for maintaining the performance and longevity of your Yamaha motorcycle. On the other hand, if you're uncertain about your skills or don't have the time, it might be worth considering taking it to a professional shop for the rebuild.

Details:

Yamaha YZ250FX 4-Stroke 2015 -2019. Piston comes with rings. Everything for a top end rebuild in one box. NOTE: Image is for reference only, actual product may vary slightly depending on your specific application.

Comes with enough components to service one engine. Namura Top End Repair Kit 76.96mm Size A #FX-40037K Yamaha YZ250F/YZ250FX/WR250F: top-end repair kit can help improve the performance of your ride and keeping it running in peak condition. Top end gasket kit.

part #: fx40037k prices

• $187.28-$190.72

specifications pistondon:

• for models: Yz250f, Yz250fx, Wr250f
• for makes: Yamaha
• brand: Namura
• mpn: Fx-40037k

offer pistondon:

• options: Ship-to-home
• quantity: 2
• sold: 0
• availability: In Stock
• started: April 6, 2026

general pistondon:

• condition: New
• Motorcycle Scooter Parts Accessories > Engines Engine Parts > Pistons, Rings Piston Kits

payments pistondon:

• credit card: Visa
• wallet: Apple-pay
• other

shipping pistondon:

• cost: $0.00
• transit: 2-4 Days
• service: UPS Ground
• type: Fixed
• class: Standard
• carrier: UPS

seller pistondon:

• # reviews: 697129
• city: Grand Rapids, Michigan
• rating: 99.8%

returns pistondon:

• time: 30 Days
• paid by: Seller
• policy: Returns Accepted

Namura FX-40037K Is Similar To:

• Namura Technologies Nx-40080-4os 040 Over Bore Piston Kit For Yamaha 1993-2001 Yz80 48mm (36.9% similar) Manufactured by Namura. Made in Taiwan. Kit is for .040 over bore size - 48.00MM. Compression ratio of 8.2:1. Piston dome is anodized for superior heat resistance and longer lifespan. Piston is 47.95MM. Compatible with yamaha model's below: 1993 YZ80. Kit includes piston, rings, pin...(August 11th, 2024)
• Namura Technologies Nx-30000-c Piston Kit Standard Bore 53.96mm (29.7% similar) Bore: 53.96MM, sizing: standard bore, MOS2 made with Teflon /molybdenum coated skirts - a rolled on application process provides a fits bond...(August 12th, 2024)
• Namura Technologies Nx-30004 Size A 53.94mm Piston Kit For Suzuki 2001-2003 Rm125 Standard Bore 54mm (30.5% similar) Benefits include increased heat transfer, reduced friction and helping to eliminate cold seizures. Some tests have shown this feature can increase horsepower and fuel economy by up to 6%. Machined smooth heads - reflects combustion heat and reduces carbon buildup, protecting the top of piston...(August 12th, 2024)
• Namura Technologies Nx-30025-b Piston Kit Standard Bore 66.95mm (29.7% similar) Anodized domes - increases heat resistance and durability; pistons with anodized domes are 75% stronger than non-anodized. Machined smooth heads...(August 13th, 2024)
• Namura Nx-10051-2k Top End Repair Kit 0.50mm 39.5mm 10.0 1 Honda Z50r crf50f xr50r (54.7% similar) Everything for a top end rebuild in one box. Comes with enough components to service one engine. Namura top end repair kit 0.50MM 39.5MM 10.0:1 Honda Z50R/CRF50F/XR50R: top-end repair kit can help improve the performance of your ride and keeping it running in peak condition...(August 14th, 2024)
• Namura Technologies Nx-30016-b Piston Kit For Engine Pistons Kits Aw (31.6% similar) Namura NC-30016-B piston kit for engine pistons kits aw: status: in stock...(August 15th, 2024)
• Namura Technologies Nx-20013-b Piston Kit Standard Bore 48.46mm (29.7% similar) Bore: 48.46MM, sizing: standard bore, MOS2 made with Teflon /molybdenum coated skirts - a rolled on application process provides a fits bond that is 10 times stronger than other spray coatings. Actual product may differ from the item shown in photograph. Benefits include increased heat...(August 15th, 2024)
• Namura Technologies Nx-70020-b Size B 39.47mm Piston Kit For Ktm 2009-2016 50 Sx Standard Bore 39.50mm (27.1% similar) Made in Taiwan. Compatible with KTM model's below: 2009 50 SC. Piston dome is anodized for superior heat resistance and longer lifespan. Kit includes piston, rings, pin, clips you get exactly what is pictured. Size b piston is 39.47MM. Kit is for standard bore size - 39.50MM...(August 17th, 2024)
• Namura Technologies Nx-40008-2r Piston Rings 020 Over Bore For Yamaha 1983-2006 Pw80 And 1986-1990 Bw80 47.5mm (32.8% similar) Compatible with yamaha model's below: 1983 PW80. Made in Taiwan. Rings are for .020 over bore size - 47.50MM. If you are replacing rings on more than one piston please change quantity in the listing. Manufactured by Namura. Includes two compression rings. Sold per piston...(August 17th, 2024)
• Namura Orna-ra426627-gs 1997-2004 Yamaha Xtz 600 Dirt Bike Piston Rings 95mm (30.1% similar) 1997-2004 yamaha LTZ 600 dirt bike Namura piston rings 95MM: ring set contains: ring to match a single piston. Parts without fitment are to be assumed universal and may require vehicle modification. I need to exchange an item.: brand: Namura, model number: ORAN-RA426627-GS...(August 17th, 2024)
• Namura Technologies Fx-40032-b Forged Piston Kit 76.95mm 2001-04 For Yamaha Yz250f Wr250f Std Bore 77mm (53.9% similar) Fits: 2001 WR250F. Namura forged series piston. Namura exclusive forged alloy used offers lower expansion rates, allowing for tighter build tolerances and superior tensile strength at operating temperatures. All Namura forged pistons come with Namura signature features: 100% CBC-machine piston...(August 18th, 2024)