Out of curiosity, if you have these 640 LC Sleeves, can you measure from the Top of the Sleeve to the bottom of the Ports in mm?Thanks everyone for the info. RotaxFlyer you were a great help, you definitely know your ski-doo's.
So it looks like I have a pair of cylinder sleeves for one of these 76mm liquid cooled engines I won't be needing. If anyone has a use for them let me know.
A New Sleeve comes undersize so you can Bore and hone it to your desired 76mm Piston after it's installed. The photo on the right the Big Port bottom 72.4mm is in the realm of a 70mm Stroke! As is in the first photo Transfer Port at 71.3mm! The first photo large port has me confused, I'm going to have to dig out a 670 Cylinder and look at it, it's been a while since I looked at one.
Never heard of one myself. The Case looked just like a 1993 670 Case. I did find the other 640 FL 1050 Sleeve on ebay.Was there ever a liquid cooled Rotax that had piston port induction ???? I am thinking not ?? Both the sleeves in pic have piston port intake ports.