RE: OS Max 60 FP Not Running
My 60 fp is a sweet engine. Gave me trouble only once when I replaced the carb and didn't have the airbleed screw set right. Other club members have noted how impressed with its performance -power and transition.
I've had it on a big swamp buggy, PT60 trainer, and back on the swamp buggy. Very reliable for me for 8 years.
I did lap the piston/sleeve before I used it, more or less did a complete teardown when brand new. You would not believe all the little filings that I got out of it.