Hey Jim! I would take your cylinder in to a machine shop and have them measure it. Just because it looks good doesn't mean it's in spec.
Maybe I'm just weird about things like this but I would replace all the bearings in your bottom end. The last two XR600s I built got all new bearings, new connecting rod, overbored piston etc. I guess I just feel since your in that far, might as well put new stuff in so you won't ever (hopefully) have to worry about anything going south.
The original engine from my '84 XL600 had about 22,000 miles on it when it lost a mainshaft bearing. Not real common but it happens. How many miles on your engine?
2005 KTM 525EXC-2000 Buell M2 Cyclone-1996 XR600R-Plated 1995 XR600R-1993 Kawasaki KX500-1984 Honda XL600R/XR650L Hybrid-1984 Yamaha TT600L-1980 Honda CB750F