Spend $250 to get free shippingSpend $250 more to get free shippingCongratulations! You get free shipping.
Shop with confidence
Fast shipping
Easy exchanges
Trusted reviews
Expert Support
Refresh your two-stroke engine's performance and reliability with the Vertex Top End Piston Kit (Part No. 0910-3362 / VTK22521B). Recognized globally as an industry leader in OEM-replacement replica pistons, Vertex manufactures these gravity-cast pistons from high-silicon aluminum alloy to ensure exceptional dimensional stability, reduced friction, and precise cylinder wall sealing. This comprehensive kit includes everything needed for a complete top-end service: the cast replica piston, rings, wrist pin, circlips, a complete top-end gasket set, and a high-performance wrist pin bearing. Engineered to strict tolerances, it delivers restored compression and crisp throttle response for demanding motocross and off-road riding conditions.
Fitment Table
Year
Make
Model
Position
Notes
1998–2001
Kawasaki
KX250
-
-
TSO Tech Tip
When rebuilding your KX250 top end, always replace the wrist pin bearing alongside your new piston and gasket set to prevent unexpected needle bearing wear. Measure your cylinder bore carefully to verify proper clearance, thoroughly clean any carbon buildup from the KIPS power valve assembly, and apply a light coat of two-stroke oil to the piston skirt and wrist pin before final assembly.
Compatibility
Fetching compatibility details...
Year
Make
Model
Customer Reviews
Overall rating: 4.9 / 5 from 58 reviews.
Shipping was fast, the product is great!
When you could still buy the shift forks from Kawasaki they came out of spec :-(
These are in spec and far better quality than Kawi's forks.
They are in the bike and vastly improved the shifting on this KX500 BEAST!!!
Thanks Luke!
Unfortunately, the gas cap got scratched during shipping,
but after a few friendly emails, the problem was resolved perfectly for both sides.
Friendly service, quick solutions, absolutely reliable
Top-notch shop👍
Everything I have received from TSO has been excellent, I was excited to see TSO had the pressure plate because they was the only ones , thanks for amazing products and service
Very well made pipe fits good have not been riding yet so don’t know if it leaks out two stroke oil like the stock one does we will see when it gets cool out for riding
Very quick shipping, and super pleased with the quality of this stator cover! The anodized black blends nicely with the satin black powder coat on my KX500 engine.
Quality parts!!! Very happy with what I received for the money!! Fit and finish is top tier. Also happy to support a company who is helping keep these two strokes alive! I will be back for more parts soon!
Bearings were a perfect fit. A couple of shaft bearings were on back order, which I reicieved shortly after a majority of my orders arrived. Quality of everything is immaculate I would certainly do business with Luke again. I honestly wish I could have purchased the billet cases for my kx500af build after seeing the precision on the covers and head. Highly recommend TSO
Haven't installed these parts yet but the maching and quality looks better than OEM. Looking forward on trying out their other specialized parts offered.
I ordered the case saver for my 98 kx250, the price of the TSO case saver was very close to the same as the original kawasaki one.
The difference is huge, The TSO case saver is made of stainless steel for extra strength and great looks.
Shipping and customer service was very fast and included mounting hardware.
First time I ordered from TSO, but it won't be my last.
Thanks TSO for offering a quality part and great customer service!
So the cylinder head is immaculate and performs perfectly with the decompression valve. Much much easier to start this 500cc 2 stroke. I just wish I the decompression valve was coming off the side instead of straight out the top. Decompression valve creates interference taking out the spark plug when everything is mounted and the bike is together. Purchased a new wrench to remove the spark plug and all is ok. Overall happy 😁