ORIGINAL: Hobbsy
Brian, I think people hear the cam followers rattle in the Saitos and panic thinking it is the bearings, I put a new jug on my 1991 1.50, I broke it tightening the carb too tight, but I left the stock bearings in, they are fine. They are still fine in my 1992 .80.
You're probably correct in that Dave. Saito's do have a bit more mechanical clatter than the OS/ clones do. Novice modelers tend to be alarmed at this but they can be rest assured it is fine as long as yourvalve lash is ste within specs. To the veteran, it is a much different clatter than the whirrr or growl of a bearing going bad.
I like to set my valves following the first gallon or so on any 4-stroke to about .0015", on saito's it quiets the valve train down a bit and on all 4-strokes it reduces the amount of lifter bounce when on the trailing ramp of the cam, and increases the "snappieness" of the low-midrange throttle response.