my 1987 kx 250 is missing the rh power valve and it is discontinued. i have a 1988 jug and was wondering if it will fit on my 1987 lower end? thanks Alex

I am not 100% certain, but I don't think so. The top end was revised in 88 to a 3 piece KIPS valve, where the 87 was only 2.

IIRC there were a lot of small revisions that would make it unlikely. I can check a bit more later.

Cary