jackster,

I've had a couple .52s and they are super little engines. They have also been very easy handling with one exception....they HATE any plug but OS four stroke plugs. Have not found another variety that provided good running characteristics at both top end and idle...at the same time. So, if you can tune for top-end but loose reliable idle...or vice versa you might want to switch to an OS F plug. That is if you aren't currently running same. BTW, plugs can be born funky, so it might be a good idea to try another plug. Again...if you haven't done that already.

I generally run 5% two-stroke fuel for the extra oil...sometimes 10% two-stroke. Needles set a little on the rich side.