OK, NOW WE ARE DOING "i THINK" stuff.. think... low speed cold idle is where the airflow is MOST criticle, to make a bike run.. not wide open.. a clogged filter will not idle, but will run at higher rpms, when warm.. once the engine warms, the air in the airbox is warmer, and will allow airflow thru the congealed goop, on a cold air filter.. once warmed, it softens, and melts a bit, and air can be supplied..
any bike can run well when it's pressed and at high rpm, not so much off idle, or cold.. and being fuel injected, and not having the same issues a "jetted carb has", air is the prime factor. Now, that said, if valves are "off", they also control flow into the cylinders, but really don't change the performance as much as the "available air just off idle", that a combo of tight valves, and a restricted filter do.
there is method to my comments, I have been doing this a while.... not trying to be "snippy", but the airfilter controls a lot more than most people realize on this bike. IMHO it's marginal for its longevity, and needs regimented, and regular attention to make the bike run right.
So Please, take this from someone who HAS done their own service, in timely manners, and has been inside of the "plastic wayyyy to many times to count". Again, if you have not actually "done" the work, it's a bit hard to swallow advice on what may "seem" to be the issue... kinda like playing the blues, without paying the dues.
Oh, and PLEASE, refrain from dumping chemicals into the fuel.. it NEVER helps diagnose, or correct an issue, it just masks underlying issues for a tank of fuel.. bump the cold speed idle up to 1100rpm, at startup, via the adjuster knob; it will drop back once warm... Insure clean fresh fuel, and a clean air filter.. and run from there.