[Hotfingrs]

Bryan

Are you running a choke. I don't and mine backfires til it's warm. Solution is to keep the rpm's up for a few minutes until engine gets warm.

If you are using a choke, check the settings and make sure that it's working, and also see if you can get it to close a little more, to richen the setting

Don't know if you have the houseing on the side with 3 screws to hold choke adjustment....but if you do loosen them a little so you can turn it. There should be marks on it for reference points. Just richen it a little at a time to make sure your engine will run when cold.