I've tried everything, still way way rich! help please

[maireeka]

Ever since i unplugged the hole in my main jet she's been running holy cow rich. i've tried lowering the float to the point that there was no gas in the carb at all, no change. I tried tightening the pilot screw all the way in, no change. Did I "open up" the jet when I unplugged it with a needle? What else could I look at?

Does the idle screw affect mixture at all or is it just the fuel screw? What about the needle clip? it's on the 2nd slot from the top.

 

[autoguy]

how do you know its running rich ?

have you done a plug chop ?

is the bike bogging ?

it sounds like you need to go down a jet size or two

what bike ?

 

[maireeka]

1978 cb125s 1cyl

New pilot screw, main jet, floats, needle valve, spark plug, coil. Plug gap and points gap are set. Float level should be set right, but I've never done it before so it may not be right?

whats a plug chop? when the plug is CLEAN it starts on the first kick. Idles shitty for a few seconds and dies. I then pull the plug and it is black, sooty, and wet with gas. Plug normally needs to be cleaned for it to run 2 times in a row.

It seemed like back when the main jet was clogged, it was leaned out enough that it would run at partial throttle. WOT works fine now that the jet is fixed, it's the low rpm stuff that isn't worth a damn.

I can't tell if it's bogging per se, it runs like utter shit. It's nigh unrideable since I fixed the main jet.

That makes me think it's rich.

Just replaced the main jet #110 (stock spec) and didn't really fix anything.

The only other things it could be is float level, pilot screw, and needle clip, right? If the pilot screw is all the way in then the fuel is as low as possible I believe.

Another thing: i'm still running the points that came on the bike. I figured I'd leave em alone because it ran ok at one point, and the points being effed up wouldn't make it lean or rich. Seems to def be a carb problem I think.

 

[Terry]

No, bad points won't make it lean or rich but without quality spark there will be no combustion. If it were me, I'd put every jet back to stock and double check the carb cleaning and float height, replace the points, the spark plug wire and cap, do a valve adjustment, adjust the timing chain tension, meter up the coil to make sure it's within specs, make sure the battery is fully charged and clean every damn connector I could lay my hands on. Essentially, start over. You got nothing to lose. Also walk away from the bike for a couple of days and allow your head to clear from the frustration. My XS650 gave me a run for my money when I first got it, so I did something else for a week and then tried again. It helped me a lot and I got the thing running prtty good.

Terry
J'ville, Fl.

 

[autoguy]

yer running rich thats for damn sure, other than going down a jet size or two, get a hand full of jets and try them and go from there, have you tried adjusting the air fuel mix screw to lean it out ?

have you checked to make sure the carb body bolts are tight to the intake ?

 

[maireeka]

this carb doesn't bolt onto the head, there's a rubber boot bolted to the head and the carb clamps into it. I'll check all of that but I'm pretty certain that it's all tight.

I feel like with no air cleaner and no muffler, the stock jet should be LEANER than it should be, if anything. This is why I don't want to muck around with getting a bunch of jets, because it seems like jetting isn't the issue.

I'll screw with float height next because I don't know if I actually know what I'm doing on that one.

The air fuel screw is lal the way in, which should lean it out as much as possible.