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Discussion Starter · #1 ·
Iv had it for 2 years now use to run mint no issues last year it lost spark so I got a new stator that didn't do it so I got a cdi box an a voltage regulator finally had spark tryed to run it an it only stayed running if the idle was cranked up to much an it would pop like gasp for air and die. Cleaned the carb an the air mixture screw I believe was bent an rusted so I baught a new carb hooked it up an it does the exact same thing. I don't get it
 

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Did it sit for long between breaking down and getting going again ?

The reason I ask is, if it was going then lost spark, and you got it going again within a few weeks or so, then the carby shouldn't have developed a problem, and so the no idle after getting the ignition fixed would seem to be caused by the new ignition setup. If on the other hand it sat for a year, then yeah perhaps the carby did develop a problem from sitting.

If it was a short sit broken down then I'd suggest you recheck the cdi is right for the bike, that the ignition timing is correct, and that the charging system is operating properly ie, charging and regulating. I'd check the sparkplug too.. it might have got fouled when the spark was dying.

Otherwise it sounds like the carby/fuel system needs checking over. Is the fuel fresh ? Does the choke make a difference to the running ? Even though the symptoms seem the same since changing the carby, are you sure it hasn't got an air leak between carby and engine ?

The idle mixture screw on your old carby would have been made of brass, so wouldn't rust, and wouldn't get bent, which makes me think you are not familiar with carbys, so I'd suggest you get the manual and have a read up on the carby, familiarizing yourself with what all the parts are before going any further. You need to identify the idle mixture and speed screws in particular.

Then you could try draining the fuel from the carby using the drain screw on the bottom of the bowl, then when it's empty turn the fuel on and make sure it flows out the drain at a good flow. If it's getting plenty of fuel through the carby then it probably needs adjustments made to suit your bike. The first thing to do is try adjusting the mixture screw. To adjust the idle mixture you will need to back the high idle down to somewhere nearer it's proper slow idle speed. Start where it is and see if the mixture screw makes a difference, if it does then set it to the best idle and then back the idle speed down and recheck the mixture, then slow it and recheck the mixture, go around getting the idle set to it's best running position with the idle speed set as slow as possible. If it idles you should try riding it, and you may find you need to make other adjustments to make the bike run right with throttle, and if you do those adjustments you will need to reset the idle mixture again.

Unfortunately aftermarket carbys are seldom setup to run right with every bike, and nearly always need changing to suit the particular bike, climate, and fuel being used. When I have to change carbys I usually strip them and check the jets are all the same size as the original carby's jets. If they aren't then I swap in all the old jets, plus the slide needle. It's absolutely essential though that all the jets get changed, you can't swap some of the jets and expect it to run right.
 

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Discussion Starter · #3 ·
It sat for the winter an I got the stator in like may it spit an sputter with the old carb an I cleaned it 6 times taking everything out the brass for the choke was scratched an crusted up and the air screw was too. Today with the new carb it starts up when it wants an we had it idling high then when turning it down it popped an died. But it revs up nice just chokes out when it's low
 

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Try adjusting the mixture then.. It needs to be set to it's best running with the idle speed as slow as possible. Once the mixture is set right at a low idle speed, then you can speed it up slightly if needed, but don't touch the mixture again.
 
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