Motorcycle Repair: Surging Issue, oxygen sensor, custom maps

Question
QUESTION: I have a 2012 Heritage FLSTC. I did a Stage 1 with Hyperchager Pro R air filter, Bassani 2 into 1 Road Rage Exhaust, & Cobra Pro Auto tuner. Bike runs fantastic, however on smooth slow acceleration, to increase speed up from 60mph to 65/70mph I can feel a slight surging but can not hear it in the exhaust. When you ease off the throttle it goes away. If you accelerate fairly hard it doesn't do it. Shop has said it could be the air filter, the oxygen sensor or bad tuner. I placed duct tape on front half of air filter to reduce air intake from the butterflies,but that did not help. My buddy has a 2013 FLSTC with same stage 1, except he went with Rush Dual Exhaust,and we are both having the same issue. Only his is much more surge than mine. The mechanic contacted Cobra and they had him do some adjustments to the Tuner which did not help. They implied that they have had this issue before, but are giving the run around. Any input or help would be greatly appreciated. Thanks

ANSWER: What tuner is your buddy using?
Mike

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QUESTION: Same tuner "Cobra Pro Auto Tuner"
Rick

Answer
Since both of you are having the same issue and both have the same tuner, I would say the problem is the programing with the tuner. I have never used this tuner, I write custom maps for Harleys, so I am not familiar with it. About the only thing you can do is either keep bugging Cobra or go with a different tuner.
Sorry I couldn't be more help
Mike