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Usually the pilot jet is the problem since it had such a tiny orifice down through the center.
Open the mixture screw 1 turn to see if it changes.
Or a vacuum leak at the carb boots. Spray carb cleaner on the boot and see if it improves.
 
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Discussion Starter · #3 ·
Usually the pilot jet is the problem since it had such a tiny orifice down through the center.
Open the mixture screw 1 turn to see if it changes.
Or a vacuum leak at the carb boots. Spray carb cleaner on the boot and see if it improves.




Which screw will that be? When I get off work again and it's daylight I'm going look everything over
 

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The green one is idle speed and the red is the mixture screw.
If there is a plug over it like in the picture,drill through GENTLY, and pull it out.

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The factory plugs it when they set it up a bit lean to pass emissions standards.
But we take them out to make the bike run good.
Things change in an engine after some years, so it needs to be adjusted for better idle and low speed .
 
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If that tamper plug is in, that is a screw for altitude, not emissions. You'll most likely need to see if the slow jet is clogged. Buy a can of gunk brand carb clean. See if you can spray cleaner thru the slow speed jet. With the nozzle that comes with the can, shoot that hole in the carb, or the most forward at the cylinder head side of the carb holes. Rather address it initially there first, then use a carb cleaning chemical added to the gas, and see if it will loosen up the possible varnish at the needle tip. If that slow jet was clogged, there is your idle coming back.

My suggestion is to never touch that screw behind door number two.

Signed,
Go head make my day
 

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Discussion Starter · #8 ·
If that tamper plug is in, that is a screw for altitude, not emissions. You'll most likely need to see if the slow jet is clogged. Buy a can of gunk brand carb clean. See if you can spray cleaner thru the slow speed jet. With the nozzle that comes with the can, shoot that hole in the carb, or the most forward at the cylinder head side of the carb holes. Rather address it initially there first, then use a carb cleaning chemical added to the gas, and see if it will loosen up the possible varnish at the needle tip. If that slow jet was clogged, there is your idle coming back.

My suggestion is to never touch that screw behind door number two.

Signed,
Go head make my day

I took the carb apart already to clean it because had trash in it than I put it back together an put it back on bike now want run on idle
 

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Don't touch the idle mixture screw?
That is pretty hard not to do when the engine has changed and maybe the air filter and exhaust are no longer stock. Valves are carboned ,compression changes, carbs have leaky throttle shafts, timing chins wear, etc, etc.
I want mine to run the best and have good off idle response.
 
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Discussion Starter · #12 ·
Don't touch the idle mixture screw?
That is pretty hard not to do when the engine has changed and maybe the air filter and exhaust are no longer stock. Valves are carboned ,compression changes, carbs have leaky throttle shafts, timing chins wear, etc, etc.
I want mine to run the best and have good off idle response.

Could a broken choke cause the dieing issue
 

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Allen, that was something very specific I asked, meaning, every circuit has to be open to idle. Choke is a purge of fuel to ignite a cold engine. So again, question was not answered to the its flow ability. Sure, moving the green varnish off the body of the jet says clean to you is not showing how clean is the spray. One fuel circuit is down it wont idle too well if not at all.

Either of the 3 circuits will cause hard starting, no idle is that showing 1 is not flowing. There is no mention of it being modified, swifty. It ran out of the crate no problem all this time, now it sits, now is not the time to ruin the tune is this guy has no clue if you can tell. Lots of theory is not present. May have the mechanical aptitude, but it takes a little understanding about vacuum, fuel circuitry, and it snowballs from there.

If it's plugged up, then leave it plugged. Chemically clean it then riding it with an additive.
 
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