Hi adnansanni
There could be many factors for the vibrate or not smoothly forward. Below is a possible list (totally based on my experience) -
1) Not proper clutch release (maybe you're used to your previous bikes clutch release, and as Uni is new, it will take a bit to get used to)
2) Your bike is totally new, thus the clutch plates needs to get free
3) Clutch cable could be tampered
4) Check spark plug, for proper current (whether it mis-fires or not)
5) Check for the engine oil
Everything else, you have a very good ride, so enjoy it and have a safe ride
