Okay so last Thursday I was riding home from Uni going up a slight incline and heard a loud pop (like a balloon but a little deeper) sounded like it was right behind me (no cars where around me or people it was quite late in the afternoon) so I was thinking a little back fire from the exhaust or something can't quite remember if I decelerated a little or not. All was fine until about 10 miles later, I was taking my exit off a roundabout, once off the roundabout I accelerated and a few seconds later my bike started to shudder as if it was cutting out like I hit the rev limiter but the speed was no where near when I would usually shift gear, The only way to stop this shudder is to shift up a gear it only seems to happen high in gears 3, 4, 5 and anywhere over 60 - 62 mph. Went to my local dealership and told them my issue and they thought it might be a clutch issue, they think the clutch is slipping when under load but doesn't clutch slipping mean that the RPM's increase but road speed doesn't, I'm not ruling it out just going by what I've read online so far, and my issue is that once it starts to "shudder" I can't go any faster or get past the "shuddering" it 's as if my rev limiter has some how changed to a lower rev range or something, not suggesting that's possible I have no clue, just trying to describe best as I can what it's like. Another thing I have come across in my search for this issue is valve clearance or wear, took my bike to get looked at by the dealer ship they had someone take it for a road test, they checked, adjusted and lubricated the clutch cable and ticked most checks and lubricates on the check list I have received but the bike has still got this problem, the only check/adjust box that isn't ticked off is the valve clearances. Does anyone know what this issue could be any help is appreciated Thank You.