Ever since I switched props I can't get it tuned. It will transition great on the ground and in the air it will transition from idle to full throttle quickly with no hesitation. BUT, like maybe 1/2-3/4 throttle,if I leave it there, the engine goes "blum, blum, blumblum, blum". (sorry it it seems stupid but trying to describe the sound). Now when it idles in the air it idles smooth and at full throttle it sounds good. Trail of smoke and oil is reddish-clear. It's just at that certain point it it seems like it's not running at a steady RPM. High,low,high,low real quick. Should it at any point in the throttle be running smooth with no change at all in RPM?

Also, if you run your low idle too low will it damage the engine or will it just die when going verticle? I know if you run the high speed to lean the engine could be damaged, but does the low speed setting have as much of an impact on engine damage?

I'm kinda of a pefectionist so I try to get things dead on all the time. So when it does this and I have no idea what it means it bothers me. AND I'm real paranoid about damaging my engine. I have spent the last two days just screwing around with the low idle screw and it still not right. But like I said, hasn't died in the air, and transitions fine even when going from idle to full real quick. Just makes a noise like it can't decide if it wants to run high or low at that point.

Can't complain though, on my 4th gallon of fuel and my first 2 flights were on the buddy box and after that I have been on my own with no incidents (besides 2 deadsticks). Even if it's windy I have no problem, totally comfortable with it.

I JUST DON"T WANT TO DAMAGE MY ENGINE!!