well i called a buddy last night about it, and he said it's pretty much usless to look for another 350 around here, cuz the valves all went on them, the 500 is too tall, and the 250 wasn't very good, so at his suggestion i'm looking for a 2 stroke to put in seeing as they're shorter in stature, and i just plain like 2 strokes. he's got an old dual shock CR250 that i may look at but i don't want to take an engine out of a perfectly good bike someone could restore, he's going to keep an eye out for anything else.
any thoughts on the 2 stroke idea? i figure a 250 2 stroke would be enough, would a 125 be suitable as well? dare i look for an even bigger one?