I had an OS 52 Surpass four stroke a few years ago. For the first start to begin break-in, I used an electric starter, and it started pretty much right away. I didn't use a chicken stick so I can't answer that part of your question.

However, if I recall, I never allowed it to get over 10,000 RPM. In fact, it was more like 8500 or so. It pulled pretty good at that RPM so I was satisfied with the performance.

I don't know about anyone else, but I would be a tad bit leary about going over 10,000 RPM just for the mechanics of the engine. The four stroke has many more parts than a two stroke engine, and that's more parts to move in coordination. And at that RPM, well, I just feel that it is skirting disaster when going above that.

The best way to control that is with a prop, and with the pitch of the prop being the major factor here. And, of course, making sure you are not running to lean, which will be a bigger detrement to that engine than RPM would be, and of course, the combination of over-heating by lean mixture, added with the 'excessive' RPM, may prove to be to much.

Most people that I know do go higher in pitch with their four strokes because of the torque that these little jewels produce. They can turn a prop with a higher pitch than their two-stroke counterparts. But, the power output is usually lower than their equal size two strokes.

Now with that said, what I would do is go ahead and make sure it's not to lean (and it sounds like it is not.. but just make sure..) and then increase the pitch of the prop until you are satisfied with the performance.

Oh.. is this engine on a plane? Or did I overlook that part of your post? If it is, then fly it. See how it performs with various props. You may be pleasantly surprized at what the performance is with different props than the 'break-in' prop.

Best of luck.

CGr.