Captain,
There are 2 totally different issues that will cause what you're describing (the hang). One is heat related, the other has to do with that 'step' in the ign. module (if you have the early module with the 4.8v voltage limit).

If it's the step that's messing with you, you can lower your idle speed a little to help or eliminate that issue. The ign. 'step' happens at around 2200 or so, and if you're set at 2000 normally, it's not too hard to see it might hang a little prior to dropping? If you have the newer module with the 8.4v limit, the step is gone. This is not your issue.

More likely, it's the temp thing. Try running your LS needle a little richer to see if that doesn't help? If it's right, the idle should be kinda lumpy. A 2 stroke single is not well known for how smooth they idle when right. There's a better explanation in the notes I wrote up in the "Newbie to gas" string at the top of the gas section here. It's the last note.
http://www.rcuniverse.com/forum/gas-...l#post11210626

Holler if you're still having trouble after that. There's a bunch of us that have been messing with these 20's for a while now....