4 stroke in a 2 stoke!

i have a 2004 cr 125 and i was wondering if it is possible to put a 250F engine in the cr 125?. if so does anyone know where i can get a 250f engine that would fit. PLEASE HELP!!!!

Why not just buy a complete 250f then??

I think an xr250 motor in a CR125 would be cool

i would buy a 250f but ii dont have the money and i was thinking i would buy a used 250f engine.

sounds like a serious project. by the time you buy the engine and weld and fabricate things together...you might as well have bought a CRF in the first place

I read about someone putting a CRF230 motor into a cr125 with very little work. I would like to try that.

get your cylinder bored out 2mm and replated. Add a Wiseco 2mm overbore piston and you have a 135!

thanks for the replys.

Yeh. for the money, doing that is unreasonable. I would look into either getting a used newer 125, boring or stoking yours out and not tell anybody(for racing purposes), and lastly because of the cost, would be getting a used 250f. I would go with a yz250f because they were the first to come out I think and you could get an older model for cheaper. I wouldnt do the conversion. Thats too much money and hassle. By the time its over with, you'll probaly be dissatisfied with it. That is if you finish it. :cry::bonk: Thats my 2 cents! :applause:

i think service honda sells motors for a couple grand

Buy a complete CRF250, take out the engine, (yes the engine will fit, but the cradle will probably need to be re-made, and new engine mounts and maybe an airboot will be neccesary. Sell the CRF250 chassis to someone interested in making a CR500AF. OR just have the 125 ported, bored, and put on a 36mm PWK airstriker carburetor, and ride it properly (you should be able to hand it to the 250f's if you do this).

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