How steady is your idle?

If any of you guys have watched a digital tach you'd know there is no such thing as a smooth idle. All engines are all over the place within about 100 or so RPMS, so smooth is a relative term.
 
Bouncy idle

As i mentioned in another thread (http://www.998cc.org/forum/gen-ii-mods/14773-kinked-fuel-line.html#post183022) the idle bounces a lot (700rpm to 1200rpm) when i start the engine while it isn't absolutely cold.

What could be wrong?
Bad gas? I almost emptied the fuel tank and filled it with checked gas but nothing changed...
Kinked fuel line? I didn't lift the tank since the dyno run i did in July where everything was perfect...
Thermowax? I think that this would cause problems while the engine is cold...
Throttle body sync? My bike has only 34000kms (22000 miles)...
Today i rode it hard and i have the impression that more than usual heat is coming from the right area under the front seat but i could be wrong...

Every opinion is welcomed...
 
Yesterday i took it to the yamaha repairman and he checked the coils, the spark plugs, the fuel lines, the throttle bodies, the thermowax and everything is ok but the problem remains...
He noticed though that when he closes the exhaust oulet a little the problem almost (not entirely) disappears... I will give him the db killer tomorrow to test again.
Do you guys have an opinion on this?
 
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