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Introducing the ultimate precision-machined cylinder head from Two-Strokes Only, featuring an interchangeable combustion chamber specifically engineered for optimal power for your riding conditions. This head boasts a raw, exposed finish that highlights the precision of its machining, coupled with significantly improved water ducting to keep your engine running cooler and harder, from the gate drop to the checkered flag.
Precision Engineering & Contents
Manufactured from a high-quality alloy for maximum durability and heat transfer.
Secure Sealing: Utilizes O-rings for a perfect seal (O-rings included).
Easy Starts: A KPMI decompression valve is included, making starting challenging engines like the CR500R exceptionally easy. Simply push the button and fire it up—the valve closes automatically once the engine is running.
In the Box: Decompression valve, 7 copper washers, and 7 nutcaps are all included, O-rings.
The Enemy of Power: Heat
Heat is the ultimate enemy of any engine, especially high-performance two-strokes. As the race progresses and engine temperatures climb, power naturally drops off. If you’ve noticed your engine losing its edge late in a moto, or you struggle to clear the same jumps you made early on, you’re experiencing heat soak.
Our Solution: Superior Cooling
For years, Two-Strokes Only has been at the forefront of two-stroke performance. Our engineers recognized that traditional stock heads, made via casting, resulted in small, rough, and inefficient water jackets that severely restrict optimal coolant flow.
Our innovation was to precision-machine the cylinder head in two separate pieces and optimize the flow of all of our heads using modern design and simulation tools such as CFD. This design achieves vastly superior flow dynamics and cooling efficiency, ensuring that the power you start with is the power you finish with. Experience consistent, race-winning performance.
Compatibility
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Customer Reviews
Overall rating: 4.9 / 5 from 57 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 😁