Originally Posted by BC_Dan

Oil on plugs usually means too much oil is being injected. Black plugs could mean the main jets are too big and you are jetted too rich.

Hesitation on acceleration, especially if it's better if you have the choke at 1/2, usually indicates the carbs need to be cleaned. Pay special attention to the pilot jet and the air screw settings. The air screw should be 1 turn out from lightly seated as an initial setting. You can turn the air screw in 1/8 of a turn at a time on each carb and see if your hesitation goes away. I have had carbs that ran great at 1/2 turn from lightly seated.