I read on one of these postings that there is a bulletin somewhere that explains how to adjust the valves on these atv's. I've got a couple 150's I'd like to check but even searching the posts I can't seem to find a detailed description of the procedure. And I mean detailed! I've done quite a bit of wrenching on car's and trucks but I'm not even sure how to access the valves on one of these things.

 

the bulliten you have read about is for the watercooled 250. ive not heard of anyone needing to adjust valves on the 150. i have one as well and havent had to do anything to it.

 

I have posted this procedure a few times in the yamoto 150 thread. If I get time later I will post it again.