Engine Trouble Idle Help Wanted

Hi, Ken MUrphy. Great looking bike.

What exactly should I do with the 1/2 inch copper tube? Which way, higher or lower, do i move the carb-top adjustment to increase idle? I have not been able to find the post by igor. can you tell me where it is? Thanks.
 
Hi again, Al.Fisherman. I much prefer pictures to words, and still I am not quite sure what you have done to the carb. I assume it is the tube attaced to the intake manifold. What is the other end attached to?
 
Hi again, Al.Fisherman. I much prefer pictures to words, and still I am not quite sure what you have done to the carb. I assume it is the tube attaced to the intake manifold. What is the other end attached to?

The thread I quoted was to do with the idle screw falling out. I stated a solution, followed by a solution... I posted a picture of the carburetor, the idle screw is as plain to see as these letters I'm typing.

Solution........

As far as the tube.. it is the tube to the boost bottle.
 
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These lil engines don't idle well you can get em to by change'n the carb,or you might try opening up the pipe,and putting a bigger end on it(stinger)These lil china girls run rich for the most part,they are also detuned from the factory,take the carb off and look at the gaskett its reduced on most of em.
The end of the pipe should be just under 5/8 dia O.D.But for stock motors 1/2 copper is fine,you will notice a good change just by doin that,egor has a slide modifacation that I've done successfuly.
The simplest way for you increase the Idol would be with the adjustment that is on top of the carb where the cable comes in.
I disagree 100%.
first of all, if you have a properly tuned carb these engines will sit and idle all day long (my 2 will anyway).
adjusting the idle by lowering/raising the throttle cable at the top of the carb is a bad idea. this can make the cable pull too much when you turn left or right, making the engine accelerate as you turn.
The best way to adjust the idle is by the idle adjustment screw.
the stock exhaust just sucks anyway and the best thing to do is replace it with an expansion chamber, or to modify the stock baffle so the engine can actually breathe. The only way the stock exhaust would hinder the idle is if it's clogged up with unburned oil.
 
one other thing to check...
Have you looked at the choke plate to make sure that it's 100% open?
sometimes the screw will work it's way loose and allow the choke plate to be partially closed even tho the lever is all the way in the open position.
 
uneducated

I disagree 100%.
first of all, if you have a properly tuned carb these engines will sit and idle all day long (my 2 will anyway).
adjusting the idle by lowering/raising the throttle cable at the top of the carb is a bad idea. this can make the cable pull too much when you turn left or right, making the engine accelerate as you turn.
The best way to adjust the idle is by the idle adjustment screw.
the stock exhaust just sucks anyway and the best thing to do is replace it with an expansion chamber, or to modify the stock baffle so the engine can actually breathe. The only way the stock exhaust would hinder the idle is if it's clogged up with unburned oil.

any adjustment can be used. how do you tune a carb w/no adjustment? pull what?100%? first grasshopper u must learn machinery and then ur opinion will be edgeamacated.
 
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any adjustment can be used. how do you tune a carb w/no adjustment? pull what?100%? first grasshopper u must learn machinery and then ur opinion will be edgeamacated.

how do you tune a carb with no adjustment?
simple....
you adjust the throttle cable up at the throttle on the handlebars.
by raising the cable at the top of the carb, you are moving the slide up (or down) making the idle adjustment screw virtually useless. the only adjustment that you need to make to the throttle cable is to make sure there not too much(or too little) slack in the cable. You shouldn't adjust the idle with the cable.
you also tune a carb by re-jetting it so it actually runs right.
adjusting the float is also another good idea to get the engine to run right.
No need to edgeamacate me on this stuff, i've been doing it for years.
 
The thread I quoted was to do with the idle screw falling out. I stated a solution, followed by a solution... I posted a picture of the carburetor, the idle screw is as plain to see as these letters I'm typing.



As far as the tube.. it is the tube to the boost bottle.

hey, Al.Fisherman, still at it i see. If you had read my earlier response to Motorpsycho, you would have known I knew exactly were the idle screw was. Instead you chose to write what feels to me like a snarky response to my perfectly honest question. It turns out the idle screw has nothing to do with my problem. Neither your "solution" nor your "solution" turned out to be a soultion. Everyone else on this site has been helpful and polite to me. I have found this, and your previous responses, hurtful and unhelpful.
 
Thanks to all for your help. Unfortunstrly, while trying to fix the idle problem, I had to deal with the stretch in the throttle cable. It had gotten so long that the throttle no longer had much affect on the engine speed. Once I get the cable fixed, I'll get back to dealing with the idle issue.
 
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