Second that from Minn Flyer. The OS 75 AX is truly a sweet engine. Mine runs like a clock!!

As far as the OS 61 SF engine was concerned, it flew it around just fine. I eventually had to remove it to replace the bearings, and in the mean time, I put a Super Tigre 75 on board. It was wierd.. the inside of the muffler came apart, the plane sounded like a sliegh bell as it passed by. Super Tigre replaced it, but the new one did the same thing. So, I put a MACS Tuned Pipe on that thing. Jeech.. plenty of power with that, but it leaked fuel, right out of the needle valve assembly. But, it still runs, I sold it to one of the club members a couple months ago, to make room for other.. new models.

Anyway, no matter, if you go for the OS 75 AX, you can't go wrong. As we both said, a truly sweet engine.

CGr