Guys I always try to stay Neutral on the issues of inexpensive (cheep) engines but, on behalf of instructors everywhere I need
to make a comment (or request) HAVE A LITTLE PITY ON US it's one thing if you are an engine expert and don't mine "TINKERING" OR WASTING time figuring out why or how the engine MFG did not do his job in the QC dept, by all means Tinker away ,but if your new to engines buy quality and give your club members a break.

When a student show up at our field with a good Quality engine like OS (and a few others)we all fight over who's gets to train him, because we know we will actually get to teach FLYING, not how to dead stick his plane 20 times or spend hours(SOMETIMES DAYS) trying to fix a problem, only to send him home with a list of possibles FIXES...." change lines, get new Oring, seal up carb,backplate, New Carb , change muffler pressure , get pump, or the hundreds of other possible modification needed to make the BARGAIN ENGINE RUN RIGHT.

Do yourself a favor and Don't scrimp on the engine and enjoy what you came to the field for FLYING. Tinkering can come later when you are bored and have the time to entertain yourself

Just my .02 worth