Super rich on #2 all of a sudden.

[Skyboy8950]

So, to stop my "pop pop" problem i've been having, I did the "highest RPM method" to set my mixture screws. I did 3 with moderate ease, but #2 was giving me problems. I took it for a ride, it was missing on #2 at idle, but kicking in at higher rpms. So pulled the plugs on #1 and #2, 2 running rich, swaped plugs, switched wires on #2 and #3, same thing, problem with #2. What could cause the carb to run rich and not be adjusted by the mixture screw? Could there be something jammed in there? Something stuck? They are clean (though I haven't opened it up this time round).

1982 GS850G

Thanks,

[tkent02]

The vacuum line to the petcock goes from carb #2 on your bike, if the petcock diaphram has failed fuel will flow uncontrolled into that cylinder, very rich. Could also be a stuck float, maybe something else internal to the carb.

[doug g]

Check the petcock vacum line as stated above. I had a similar issue in the past and lo and behold that was the cause if the issue.

[bwringer]

Hey, has anyone mentioned that you probably need a new petcock?

[Larry D]

And/or the idle air screw tip is broken off in the carb body.......

[Skyboy8950]

Really? Woah, it was working great. Shoot.

[TheCafeKid]

Petcock likely, but a stuck float COULD also be the culprit. Id check the petcock/vac line first just to avoid pulling the carbs off if you dont need to. Broken tip on the screw would make it stay where it was or lean out, not richen up.