If this question has been asked, please point me there. I have a 87 XL600R that I'm doing stuff to. I want to up the compression, but not to the 11:1 Wiesco because then I "may" have detonation problems. So the option is to use a piston from some other thumper that will fit. So, what is important in choosing a piston? I would think wrist pin to crown length. Diameter at the skirt. And total length. Is this correct? The goal is to obtain a 10:1 compression ratio for my XL with the current being 9:1. Piston diameter OD at skirt 99.95-99.98 mm(3.3937 -3.9375) Cylinder ID 100.00-100.01 mm Any ideas??? If you know of a company that makes a piston, please let me know.