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Drop pure open-class two-stroke power directly into your modern aluminum chassis. This complete, ready-to-run CR500 power plant is engineered specifically for the 2021–2026 Honda CRF450R and CRF250R frames.
Built from the ground up as a brand-new unit, this engine features our proprietary billet bottom end cases and custom billet cylinder head. Designed for zero-compromise fitment, it bolts straight into your modern chassis with no frame cutting or welding required.
What’s Included with the Engine Kit:
Complete Turnkey CR500 Engine: Fully assembled with proprietary billet cases, billet cylinder head, exhaust flange, and reeds/intake manifold
Complete Chassis Mount Set: Direct bolt-in engine mounting brackets and hardware
Exhaust Mounts: Pipe hanger brackets
Fuel System Conversion: Modern EFI tank fuel pump delete block-off kit
Cooling Hardware: Custom cooling lines and weld-on radiator crossover fittings
What’s Needed to Complete the Build:
To get your swap fired up and running, you will need to source or supply the following components:
Exhaust: 1990–2001 CR500 expansion chamber pipe, 1990–2001 CR500 silencer with mounting hardware, pipe-to-silencer rubber seal, and CR500 pipe spring kit
Electronics: Complete CR500 ignition system (MSV Racing ignition paired with an OEM CDI recommended), NGK spark plug cap, and a universal kill switch (such as Tusk)
Controls: CR500 kickstarter lever, and CR500 shift lever (stock CRF250R/450R shift lever also works)
Fitment:
2021–2026 Honda CRF450R / CRF450RX / CRF450RWE
2022–2026 Honda CRF250R / CRF250RX
Compatibility
Fetching compatibility details...
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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 😁