The carb have been jetted with k&n lunch box filter. I'm not sure what size jets they are since the previous owner did it. Anyway the bike has been sitting dormant for over 2 years before I got it. I took the entire carb apart this past weekend and cleaned everything inside out with Seafoam and carb cleaner. Put everything back together and ran the bike... here are the symptoms:
With choke on the bike runs OK, with some hesitation at first but once she gets warmed up it gets better. But once I close the choke, the bike immediately dies even when the engine is warm. With choke partially open, I twist the throttle there'll be lots of hesitation, and I can hear the carb "spitting".
Checked the plugs afterwards and seems like the bike is running way lean.
Can anyone tell me what's going on here?
I had that same problem with the idle a few days ago. When I turned the choke off it would die. My problem was that the idle was set way to low so it wouldn't even run, I just turned idle set screw and fixed that problem. My bike was also spitting and hesitating, one plug was black and the other was white. I just adjusted the fuel/air mixture screw accordingly and now it runs great. These might be two places you could start, hope it helps.
My idle screw is set pretty high right now... currently it makes the engine run at 5k rpm while the choke is on. I'll try playing with the fuel/air mixture... what should be the default setting for them? When I was putting everything back together I screwed them in with only 2 lines of thread showing.
When I set mine, I tightened them untill they where lightly seated, then back out 2 turns. I adjusted them from there. I know some people have gone 3 turns, I would start somewhere around there, maybe 2.5 I'm hoping someone else will chime in here.