Try looking at the Moki 1.80 muffler for the engine not dying.My bisson pitts muffler comes loose all the time,it is a big pain in the a##.I have tried everything loctite blue red green,permatex ultra copper,all kinds of stuff.Tonight I plan on drilling two holes thru the muffler stand off to the
center of were the bolts go thru.Then I will be able to put a bolt thru the side to make kinda of a set screw to hold the muffler on.
Anyway when my muffler comes loose the engine will not die,it will set for ever and run.You can
run the needle all the way in or out and it will not die.So if you are having the same problems make sure the muffler is tight first.