Amplified "Pop Corn" sound at some throttle levels

[hgurdus]

I have a 66cc China doll engine with about 2gal of gas run through it (16/1 ratio) Its a mix of .6 gal of 87octane and 1.4 gal on 91. At some throttle levels i have had a loud "popcorn" sound. It doesent seem like its loosing power but its pretty loud and vibrates a lot. Is this reason for concern? If so how can i fix it?

Thanks, Harry

 

[Testname111]

Sounds like its 4 stroking, honestly I just got a difrent carb air filter, as the one I was using was to thick? Switched to dish rag square held on with hair ties
Just my advice tho

 

[Greg58]

If you've run a couple of gallons through it you need to change oil ratio, 32/1 is plenty of oil, 40/1 with good oil runs well too. I would try a test run without a air filter and see if that helps, as the temperature rises a engine tuned during cold weather will be rich in the summer.

 

[Sidewinder Jerry]

Your engine sounds like this? Cool lol