Closed throttle at high revs makes a good fuel burn (idle mixture) unlikely. The effective compression ratio drops to near zero due to poor cylinder filling.

 

 Fuel molecules are very far apart. The stock Renesis maps up to 44 degree of advance in this situation. The mixture burns very slowly requiring the added advance (more time to burn). Popping and clicking is still burning mixture lighting charges in the headers (turbo?) from chambers that didn't light at all. (Misses).

 

In racing engines we didn't use the OMP and only premixed synthetic 2 cycle oil. So I jetted the idle mix real rich to keep the lube going in high rev closed throttle moments.

 

The sheets of fire out the tail pipe was a crowd pleaser as well as the explosions on gear changes. It didn't count against our 105 Db  sound limit.

 

Lynn E. Hanover

 

I had the same issue.  I cut the fuel and added a bunch of advance for high-rev/low-MP operations.  Cleaned it right up.