Re: Been out of the 2stroke game for awhile...
The hd #41 Industrial chain is about as big as you can fit without some more than ugly grinding. With the #41 you can get by with just a bit of clearancing under the sprocket cover.
Any bigger and you rub the case between sprocket and coil. No way to clearance it any more without exposing coil to weather
If more is better, then too much is just enough.
If you can't afford it, build it yourself.