I have had a Akropovic crossover system insalled on 09 Vmax with stock cans sounds great. one problem a slight hesitation when starting off. Dealer adjustered O2 levels has not helped. Any clues.

It's lean, better go for PCV or other fueler

Greggmax, have you opened up the air box? If so, that is the culprit. Akra designed the mid pipe to run stock ECU and air box. Air box mod=PC V. My o9 runs great with the same exhaust set up.
D Max