Carb issues

GDCOX

GDCOX

New Member
I have about 25 miles on my 80cc jet stealth motor running 16:1 and I can't seem to get the thing to idle. When I start it it takes a few tries and then starts and runs good, but will not idle. When I turn the handle bars it revs. up. Dark oil/fuel leaks from exhust when it sits overnight, leaves a small puddle. I have tried to tweek the carb and adjust idle from the thottle connection(can make it idle really fast but not a slow idle) 1200rpm I would be happy. I still have the stock chinese spark plug.
:-||
 
if it's revving up when you turn the bars, the throttle cable's probably too tight, or it's binding somewhere (zipties, harsh bends, etc.)

you're running it really rich, too. 16:1 is basically wrong, it comes from the chinese using regular motor oil. 24:1 should be better for break-in.

the puddle could be from the air filter. the sponge will get soaked with fuel, especially when it's so rich, and it'll drip out when it's sitting overnight.

also, if your throttle cable's too tight, the slide might be above the idle screw, so turning it won't do anything, it's just screwing in under the slide, not contacting it.

wait, i just re-read that, and you say it's dripping from the exhaust. that's also caused by an overly rich mixture. the oil and fuel isn't burning fully, so it's blowing into the pipe, and leaking out.
 
I agree with lightening the mix, and will add my usual change the junk plug. I had one that absolutely would not idle more than 2 seconds before dying. Changing the stock plug for an NGK cured it immediately.
 
Ok, I replaced the gas with a 24:1 mix, put a NGK B6HS spark plug in, loosened the throttle cable. Now when I turn the handle bars it will remain same rpm. The bike runs alot better. The idle screw at the carb has to be all the way in and turned out about a
1/8 th out to get it to idle any more it quits. Is this normal???
 
No, I am sorry I must have not worded it right. The needle screw on the side of the carb next to the tickler, now to get it to idle I have got to turn the needle screw all the way in to where it just bottoms and then back out only 1/8th of a turn any more than that she quits. Is this normal for these?
 
i've heard that on some of the carbs, the idle screw is too short, that might be your problem.

normally, idle is set about 3-1/2 to 4 full turns out.

your throttle cable might still be a little bit too tight. there should be a tiny bit of slack in it if you pull on it at the top of the carb. if your cable's loose enough already, you might have a small airleak.

when it's warmed up and running, put the choke on all the way and see if i dies right away. if it doesn't, it's an airleak.

you can also spray some carb cleaner around the sealing surfaces of the manifold and the carb. it'll sputter and die if it's got a leak. don't spray it in the throat of the carb or the filter, though.
 
Thanks, that was exactly it, air was coming in from the manifold. Now I get adjustment in the idle screw @4 turns instead of a 1/8th. Sealed the manifold with some rtv.Thanks Again.
 
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