I need help with my Carb
I built my bike last week and I tested it today and The carb worked but i didnt have any control of the speed at all I was wondering if any body could post a step by step picture assembly of a carburetor thanks. Or just explain how to do it. Any help is appreciated thanks.
I built my bike last week and I tested it today and The carb worked but i didnt have any control of the speed at all I was wondering if any body could post a step by step picture assembly of a carburetor thanks. Or just explain how to do it. Any help is appreciated thanks.
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can you be a little more specific with the symptoms? how does it not work? what did you take apart?My throttle does not wokr and i dont understand why i have tried to take it apart but that didnt elp.any advice is greatly appreciated.
Remove the air cleaner and look down the throat, inlet, of the carburetor. Twist the throttle grip and see if you notice anything moving in the carburetor. There should be a cylindrical part moving up and down as you twist the throttle. If you see no movement then you need to check your throttle cable installation. The part that moves, or is supposed to move is the barrel, or slide. It operates the needle valve which allows more or less fuel to enter the intake. I'll edit this post shortly with a link to the carburetor and details on setting up the throttle cable correctly. In the interim, do not disassemble and sand on any parts.
Tom
Here's a link for you to read on the subject > http://motorbicycling.com/f39/motorized-bicycle-carburetor-install-rebuild-302.html
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I had a similar problem when I built my bike. It turned out that I was over tightening the carb on the manifold with the screw. That was contorting the whole body of the carb enough, that the slide wouldn't go down into the carb. So it the slide was stuck wide open the whole time. I'd start the bike, then when I pulled in the clutched it would rev really high, scary high.
So thanks to these guys suggestions, I put a tiny spray of white lithium grease on the throttle body and brass slide. And I wrapped the end of the manifold with teflon tape to bulk it up in circumference, then put the carb on over that, and made sure not to tighten the screw too much. Then the throttle was able to return to closed like it was supposed to by pressure of the spring. The movement from closed to open, isn't all that much travel really, but you should be able to hear it moving up and down. And as 2door said if you pull the filter and look in, you should see it moving.
You never know, maybe loosening the screw a tiny bit would free up the slide. I originally had it screwed in really tight, resulting in the problem. Even though it seemed like tightening the carb on the manifold was the smart thing to do. It turns out its better to seal it with grey gasket sealer or silicone than over tightening it
So thanks to these guys suggestions, I put a tiny spray of white lithium grease on the throttle body and brass slide. And I wrapped the end of the manifold with teflon tape to bulk it up in circumference, then put the carb on over that, and made sure not to tighten the screw too much. Then the throttle was able to return to closed like it was supposed to by pressure of the spring. The movement from closed to open, isn't all that much travel really, but you should be able to hear it moving up and down. And as 2door said if you pull the filter and look in, you should see it moving.
You never know, maybe loosening the screw a tiny bit would free up the slide. I originally had it screwed in really tight, resulting in the problem. Even though it seemed like tightening the carb on the manifold was the smart thing to do. It turns out its better to seal it with grey gasket sealer or silicone than over tightening it
There are two grooves on the barrel slide. One is short and it is aimed so that the idle screw touches it when its at the bottom of the run. The other side lines up with a small bead or key, to keep it from turning. A dab of motor oil or light grease, vaseline even, will help you install it and let it move smoothly.
Check to see that the cable is not being pinched by the little silver washer at the bottom of the spring.
There should be, under the carburetor cap where the cable goes in, a spring, then a silver washer with a slot for the cable, and a little bitty black snap-ring (on the brass needle). Lubricate your throttle cable with some vaseline and work it back and forth, before reinstalling the assembly with the carb. It will work into the cable housing and let it move freely. Make sure no zip ties are pinching the cable housing too tight.
Check to see that the cable is not being pinched by the little silver washer at the bottom of the spring.
There should be, under the carburetor cap where the cable goes in, a spring, then a silver washer with a slot for the cable, and a little bitty black snap-ring (on the brass needle). Lubricate your throttle cable with some vaseline and work it back and forth, before reinstalling the assembly with the carb. It will work into the cable housing and let it move freely. Make sure no zip ties are pinching the cable housing too tight.
If the slider is moving make sure you dont have a bad air leak. I had the same problem and it was an air leak. With the motor running spray a little carb cleaner or wd 40 around the base of the jug around the head and ports. If you hear a change in the RPMs youve found a leak.