Good post Nopick!  I also have some footage of my quad running rich on the main.



Before I'm at Olds and we are riding slow, you can hear my full throttle spit and sputter before it can clean out.

The Mikuni TM38 you can change the main jet out the bottom of the carb.  Just pickup the tools from RMATV or such and you don't even have to turn the carb to get to the jet.  The needle is a bit harder and you have to remove the carb or just turn it in the mounts to remove the slide and change your clip position.  If your Pilot jet has to change, you have to remove the bowl and main jets to get to the pilot jet.   Nothing too hard, but you need tools for all of them.