Modding the ‘01 cr125

So as the title states, im looking to some mods to my cr125. At the moment its stock other than some swedtech reeds thats about it.

Im looking to do the dome top piston and saw eshifter has a kit but was specially for the ‘99. After emailing them they said he has a ‘01 that would work but cant find anything online.

Other than the dome top pistone any other mods that i could benefit? Im not planning on racing it and even if i do my club runs an open shifter class.

Power valves Plugs was another option but seems more work.

It might be more economical to just buy a mod Honda.

What pipe do you have on it.

That said, it’s like any two stroke really. Porting, mapped electronic ignition, compression/head volume, pipe.

Boring it out to 136cc is another option. But there isn’t really a cheap/easy hop up that I can think of unless you have the motorcycle pipe.

The best base is the 01 cylinder with legacy crank cases from what I remember. Power valve plugs are kinda tricky on the 01, but SRS’ setup seems to work well.

You could raise the compression, run higher octane and send it. That’s about the cheapest hop
up I can think of. Maybe acquire a mod cylinder head, check squish gap and let it rip.

Downside is that you’ll gain compression braking which will reduce your rolling speed into the trims.

ive looked into the boring out to 136cc but they only offered for the '99 cylinder.

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Use a good computer program to custom mod your own pipe. see

www.dragonfly75.com/motorbike/ECtheory.html