This is an excellent thread. I have the Vit 701. I have only had it for a couple of months, but the shifting issue has become a real problem. I occasionally get the slip into neutral when getting on the highway and giving it a good amount of acceleration between 5th and 6th. It rev bombs and then catches into 5th after a couple of seconds, but it is terrifying.
I also run into the bike getting stuck in neutral when taking off from a stop, between 1st and 2nd.
However, I have started having new issues with it for the past couple of days. It keeps not wanting to upshift across a few different gears, even when I pull the clutch in all the way. I am hitting the shifter to shift up and nothing happens. I have to hit it sometimes 3 times before it finally goes into the next gear, but again, this is happening during acceleration. At this point, I am ready to just find another bike. I’ve already had the issue with the ABS and traction control light coming on, which the dealer fixed by loosening one of the ABS components (which they charged me to do). Considering this crop of issues, I am ready to cut my losses.
Another possible source of the issue is something I ran into on my Aprilia Tuono which sounds very similar to what you are experiencing.
Basically, if the shifter lever does not return fully to the starting position (perhaps because your boot is under it slightly) then it won’t allow you to shift gear. On my Aprilia I adjusted the gear lever slightly upwards and the problem went away.