they both have their own pros and cons. But for the weight the 250f doesn't have enough power. I have ridden both and the 125 is more peppy and lighter and easier to handle. I have always had better times on the two strokes. They don't really have any cons.
My 16yrs. old son and I both have 2005 YZ125 and CRF250. I think there is much value riding the 125 for a few years and picking up additional skills prior to jumping to the 250F. He absolutely loves the YZ125 and I don't think he would even consider 250F until he weighs more & needs extra power.
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