Dennis, I was just about to say that I am on my second warrenty replacement TH ABC .75. The reason I had to send my old one in was due to the fact I was running it to lean. On this second go around I am going to stay with the smoke trail and keep it rich.

I am not sure if you are just speaking of the break in period or through its life duration of keeping it lean.

Dave, here is what I would suggest, contact Tower Hobbies tech support and ask them this question. Run the engine as they instruct you to do.

Blackie