The symptoms that are observed in other threads is that the bike's throttle response is too aggressive off idle, as when taking off from a stop, making it hard to smoothly and consistently launch the bike. Also, people report that starter valve vacuum out-of-sync issues causes a low-RPM vibration through the engine (think, less than 3k RPM). I hope this is what's contributing to my vibration issues that I've felt at low RPM. The reviews of this motorcycle online often include a description of how "buttery smooth" the engine on this bike is, and that's funny because this engine doesn't seem very smooth at all to me. It's not buzzy or vibey compared to some inline-4 or inline-3 motorcycles that I've ridden, but this bike is far from "buttery smooth", especially under 3k RPM, and especially at more than slight throttle openings. I saw one review where they said they can accelerate cleanly from 1k RPM! What??? Lol not on my bike you can't. If you are under about 2500 RPM my bike chatters and chugs so hard you feel like you're going to shake something apart. It's worth mentioning that I've adjusted the chain perfectly and still feel the same vibrations at low RPM.
I will sync my SVs pretty soon, and report back here on any changes to throttle response and engine vibrations. I just got my sync tool in the mail yesterday. VERY high quality, by the way, most impressive for a $39 tool from China. It's larger and heavier-duty than I expected, with gauges that are nice and large, like maybe 5 inches in diameter for the gauge faces.