I have been able to fix all of my problems in the past, but this one is new to me and I can't find it on this forum. I have a chinese two stroke engine kit I got off ebay (zoombicycles). After I took the bike for a ride a few days ago I found that fuel was pouring out of the carb. I took it apart and emptied the fuel and checked everything out and it all seemed ok. I put the carb back together and screwed it extra tight so fuel can't leak out. I went out for a ride and experienced something completely new. When the motor turns over, the bike rides like the throttle is already pulled in. When I twist the throttle, I just hear a revving sound and the bike slows down. I tried pulling in the clutch and the engine made a noise that did not sound good at all. I tried to adjust the idle screw and it doesn't screw in nearly as far as it used to, kind of like something is in the way. Could someone please tell me what to do get this thing running properly. And if it matters, I don't have that c washer that goes on pin that the throttle pulls on (it don't think it has mattered in the past)
Carb problem- bike runs and throttle doesnt work
- Thread starter ccarp55
- Start date
motorpsycho
Active Member
when you took the carb apart i assume that you removed the slide?
well, it sounds like you put the slide in backwards and it could be binding up in the carb.
unscrew the top from the carb and remove the slide. look down in the carb body and you will see a pin on the right side. now, look at your slide. you will see a short slot and a long slot in the sides of the slide.
line up the long slot in the slide with the pin in the carb.
the long slot lines up with the pin to help keep the slide aligned, and the short slot is where the idle screw seats against.
if you have it in wrong, the throttle won't work and you will not be able to adjust the idle.
hopefully if this is what happened, you didn't damage the pin in the carb or the slide.
you need that "C" washer because it keeps the jet needle from coming out of the slide. the "E" clip is used to adjust the height of the needle, and the "C" washer is what keeps the needle in place because the spring rests against the washer to keep pressure on it. without the "C" washer the needle can easily move up & down in the slide.
it is also possible that your needle has backed out of the slide (because of the missing "C" washer), which would cause the main jet to be fully open letting too much fuel into the carb.
well, it sounds like you put the slide in backwards and it could be binding up in the carb.
unscrew the top from the carb and remove the slide. look down in the carb body and you will see a pin on the right side. now, look at your slide. you will see a short slot and a long slot in the sides of the slide.
line up the long slot in the slide with the pin in the carb.
the long slot lines up with the pin to help keep the slide aligned, and the short slot is where the idle screw seats against.
if you have it in wrong, the throttle won't work and you will not be able to adjust the idle.
hopefully if this is what happened, you didn't damage the pin in the carb or the slide.
you need that "C" washer because it keeps the jet needle from coming out of the slide. the "E" clip is used to adjust the height of the needle, and the "C" washer is what keeps the needle in place because the spring rests against the washer to keep pressure on it. without the "C" washer the needle can easily move up & down in the slide.
it is also possible that your needle has backed out of the slide (because of the missing "C" washer), which would cause the main jet to be fully open letting too much fuel into the carb.
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Even though I have ridden about 80 miles with no problems, I think I have had the slide set up wrong the whole time. I had it where the pin was pointing toward the throttle cable and the black e-clip was facing the carb. Im pretty sure I should have had the pin inside of the slide so the pointy end is going into the carb. Does this sound right? And what can I use instead of the c-washer I cannot find mine anywhere.
AussieSteve
Active Member
motorpsycho has told you most of the story.
Don't try running without the 'C' washer. Buy or make another and also have a bit of a look at his thread. It might help:- NT Carb Tuning Basics.
You can get a new 'C' washer here, about half-way down the page on the LHS, for $1 + deliv.
Don't try running without the 'C' washer. Buy or make another and also have a bit of a look at his thread. It might help:- NT Carb Tuning Basics.
You can get a new 'C' washer here, about half-way down the page on the LHS, for $1 + deliv.
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Thanks a lot guys. I have seen that carb thread before and that was when I figured out that I had assembled the slide wrong the whole time. I find it funny though that i put my slide needle going into the slide from the outside and the bike has worked fine for about 80 miles haha. I will get a new c washer though and have it running in no time. Thanks for the help fellas
goodtime65
Member
I lost the "c " clip once and all I did was take a small washer the same size and cut a small slit in the side works well
goodtime65
Member
Without the c clip when you give it throttle you are only giving it more air but it is not getting more fuel
Ok I successfully made a c washer by cutting a regualar washer and it's going to work fine. One more question though, when I took the bowl off of the carb, the slide needle jet also came off with it. Is that supposed to be screwed into the carb? Because I tried to screw it in but no matter how much i twisted it just would go in.
Yes, the needle jet is supposed to be threaded into the carburetor.
With the poor quality control that these kits have, yours may be tricky to get started?
I have not encountered this yet with these carbs, but I would not rule it out.
With the poor quality control that these kits have, yours may be tricky to get started?
I have not encountered this yet with these carbs, but I would not rule it out.
