It seems to be running a bit rich all the time. I can definitely smell it in the exhaust not just on start up, but also at the end of a ride. A secondary indication of richness is that it will not start (in any temperature condition) if the choke lever is opened much more than an eighth of an inch, and even once started will not run if the choke lever is opened more than an eigth of an inch. This secondarily indcates to me that the mixture is as rich as it can handle.
There is no heavy black smoke on start-up, but there is a moderate amount of lighter colored smoke for a few seconds after start up. Start up can be difficult at times -- it cranks and wants to catch but fires up with some difficulty. If I open the throttle more than a little bit (one quarter inch to three eights of an inch of movement), it will not fire up and ceases to ignite the fuel.
When warmed up, it idles at spec rpm, but there is a bit of roughness in the idle but it does not stall. Until warmed up, it will not idle on its own and the throttle must be tended to manually.
I rule out the choke being stuck, the cables moves freely to the point where the choke lever is as open as it will go.
Runs fine at riding speeds.
This is not a sudden condition, but one that has been gradually getting worse this season. While the starting has only gotten a little worse, the smell of a too rich exhaust and intolerance for virtually any choke use during any conditions has worsened noticeably
k_enn