OK, a few years ago I purchased a motor from Tim Bushman (sp) it is a 785 stroker, built by ADA. Back in the day they used 650 cranks and stroked them 6mm. When put in a 750 I believe it made a 2mm stroke. Here is the rub. 650 cranks have an 18 mm pin and 750's are 20 and 22 for newer. I may have the numbers wrong, but the proportions correct. Weisco used to make a piston for this but no longer do, due to the 100 piston order rule they have. Anyone sitting on older pistions that fit? What I have now are shims Tim made that fit the wrist pin and take up the space, my question is do you think these will hold up? Tim said they got a racing season out of a set. I don't do any racing these days, but do ride long seasons. The shims are alum. and take up the 2mm space between the wrist pin and the 750 pistons.