CRF 250---300EX conversions

[r-exrider0003]

Has any one tryed putting a crf250 motor in a 300ex frame?? i searchd and someone said something about a YZF250 motor in a 300 frame...... does any one know where I could get a used crf motor? and what about horse power on them?

[bradley300]

HP should be around 30, or the same as a 300ex witha 350 kit, porting and a good carb. best way to get a crf motor is to buy a crf, take what you need and sell everything else. for the money and trouble, its way easier to buy a 350 kit for your 300 unless your dealing with cc rules. also make sure you can doa motor swap in your class

[hetrick425ex]

i dont think it would be a very good idea, most places have gone or are going to production rules so youd be running an illegal quad. for the power gain i dont think the hassle would be worth it. you can do alot to the 300 engines and get some pretty good results from them.
Thanks
Casey