Ok so I have an 08 Night Rod special will just over 1600 miles on it. In the last few months I have taken two trips out where I was doing in excess of 80mph and then afterwards as I got into a cruseing section of the trip I found that the bike wanted to surge a lot at regular RPMs. If I jumped on it she would respond and take off on command and at idol it was fine but again at regular cruseing RMPs was the surging. The first time I had it happen it operated just fine the next day when I got back on it. And no issues in town until again I went out of town and ramped her up good. Any clue as to what is doing? Thx in advance.