I had a rich bog last year that I tuned with some jets, needle positions. I've run great all season, commuting daily, never touched my idle. I know I was still running a bit rich but within reason. Roughly even temps between 70-80F. Ran it for hours on last Sunday and commuted fine Mon-Thurs. Idled perfect/kicked first kick all season. Really even throttle and power up and down the RPMs.
I dialed my air screw 1/4 turn to lean it out as in the past few weeks prior I've noticed quite a bit of backfiring (more than usual). Because my throttle-needle in in the highest (or lowest?) position when I lean out my air screw, I can not lower my idle speed as I'm at the extreme of the idle screw so it was idling a little high. That was the first thing I noticed about 2 weeks ago but again, it was running really solid, daily.
Tried kicking last week on way home from work after a fine morning commute and I fouled a plug. It wouldn't kick and when I pulled it, it smelled like gas, pretty sooty. New plug started right up but the bike was running really bad. Sounded like it was missing firing or something but I got it home.
Sunday morning I put in a new plug, and it kicked right up but as soon as I went to give it gas, it wanted to flub-out on me. Like it was choking on gas maybe. Or not getting enough. Not sure. So I drained the float bowl but that didn't help. Neither did cleaning the fuel filter. Sooty plug again.
Now it will kick over, and the idle will be wild. It'll race, then it'll settle down. If I give it gas it sounds really raspy, some snapping-popping at times, but past 1/4 throttle it wants to give out on me. Then it'll stall out and won't kick over for a little while. This is in neutral. If I put it in gear and try to go it'll feel like it's getting gas, then not. Forward-pull, forward-pull, then nothing, then pull, then nothing. Lurching forward. Dialing the air-screw does not help.
I'm a complete loss. I spent so much of last year dialing in the carb and like I said, for months now it's been running GREAT. No wild temperature swings. Just a really quick onset of this issue. My first thought is I'm way to rich, but WHY would I be SO rich all of a sudden after months and months of no issues? That makes me hesitate to mess with any jetting right now.
I'm ready for some ideas. Let me know what you think.
Thanks/Boggy