i went through all this with my dirt bike friends. fortunately one of the guys worked in a lab that tested oil. he ran test on all the brands. they all tested prety much the same except some had a high ash rating. klotz and bellray being the worst for ash. surprisingly wallmart sentech had the lowest ash raiting and fell right in line with all the rest for it's lubricating properties. iv'e been usig it ever since.