Reading davebo's post in the thou section entitled-starting on the button, ive made a few observations recently on when my 600 has & hasnt started on the button.
My bike has always started on the button,choke first thing but no throttle at any time.
After recently fitting my K&N air filter it no longer did it,now needed just a little throttle.
Then fitted my simmi end can yestaerday & hey presto....back to starting on the button again
So taking the ability to start on the button as a general indicator of being in tune.
What is my pea brain deducing-well could it be that with the k&n there was greater air flow into the bike but not enough out through the standard exhaust & it was enough to upset the balance.
Then getting the new exhaust has increased the flow out through the exhaust enough to match the air flow in & is now back in harmony??????????