Quote from Deleted user on January 4, 2019, 7:03 pm

With the engine warmed up, I want you to pull up your AFR on large gauges.  Watch that as it begins to shudder.  From your log it looks like it is going lean and then the unit goes rich to compensate.  This is an Accel adjustment.  Go to your Accel menu and increase the Accel enrichment by 10.  There are multiple temp ranges for adjustment.  Choose the one near your engine temp.  Test again and adjust more until desired results.  Ideally you want your AFR to go slightly rich when you roll into the throttle.

Fyi. Fast Accel is for hard throttle changes.  I usually to Accel first then Fast Accel for minor adjustments to launches.