Yes, I had the same problem but wasnt concerned about it, after removing the choke from the bracket, and the carb to jet it, when I got it back together the choke worked fine. I was thinking the big nut on the back was a little loose. never really paid any mind to it.I just fixed this today on my '01 600, it was doing the exact same thing. Immediately behind the knob, use your hand and tighten down the nut. Not the nut on the 'other' side of the chock bracket, but your side. It doesn't really look like a nut, but it worked like a champ for me. Good luck.