For a couple of (maybe several) years now, my choke lever has had a grinding sound/feel when I moved it. I figured there might be some sand in it or something, but didn't worry about it. A little while ago my choke cable snapped at the top end, so I got a new cable. Two nights ago I finally got around to replacing it, and figured I would clean the grit out of it. As it turned out it was fairly clean inside, but I found the real source of the grinding.
As you can see below in a picture I stole from an ebay listing, there is a little ball in the lever. There is a spring behind it that presses it against the switch housing. I'm guessing its purpose is to prevent the lever from rattling. In any case, the ball had seized to its spring, and instead of rolling along the switch housing, it was grinding a shallow groove in it. I freed the ball from the spring, shot a little aerosol lithium grease into its hole, put some white lithium grease on the housing where the ball is supposed to roll, then reassembled everything. I'm not sure if the ball is rolling or sliding on the housing, but the lever's motion is now nice and smooth, better than I remember it ever being.
