My 2013 Ninja 1000 is stuttering when given heavy throttle input, but only in second gear. The bike also had trouble priming the pump when turning on, so I thought these were related. I got an opinion from a couple shops and a friend to replace the fuel filter and fuel pump. I've replaced the fuel pump and filter, reconnected everything. The pump primes when turning the key and switch and starts up nicely. The bike rides perfectly smooth and gives expected power output in 1st, 3rd, 4th, 5th and 6th gear.
However, when shifting into 2nd gear and trying to force out some power the bike stutters and does not catch up. If I give a slow steady input with clutch this doesn't happen. The bigger issue is that if I stutter the bike then try to shift up or down the transmission gets stuck and I have to give it a bit of smooth power, before it'll realign and let me shift.
One other problem--which I don't believe is related is that my shifter is slightly loose due to a worn dampener from loading my full bodyweight standing on one peg. I don't think this is related, considering I don't have shifting problems in other gears. Fuel pump, filter, oil, oil filter have all been replaced, coolant is full as well.
