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Baja 49cc won't run with choke off

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I soaked the carb parts in Chem dip for about an hour then sprayed and cleaned with carb cleaner. I am still having the same problem. Does not matter what the throttle position is if the choke is off it dies. Also I almost have to cycle the choke between full and 3/4. Please help. Do I need to pull back apart and soak over night? Rebuilding the carb made very little difference. When I pulled it apart nothing seem gummed up. It looked like it's been recently rebuilt.

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It is probably running lean, adjust your air/fuel mixture screw on your carb and make the mixture richer. The screw is the one without a spring on it (the one with a spring adjusts your idle).

Good luck.

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Is it the little yellow Baja 50 from Canadian tire or pep boys if your American I think... If so it could be a couple diff carb issues. To start did u fully disassemble the carb to soak? When u reassembled did u set your air mix screw to 2 turns out as a base line and your fuel mix to about 1 3/4 turns out (never spot on but a good base line at my elevation) and lastlyif you did these than check your air filter is clean and check for air leaks in the gasket between the carb and intake manifold and the manifold and head. If none of these seem to be the issue there are a few more things to check I can post later. Hope this helps.

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It's a red and white one but yes the pep boys one I have played with both screws from all the way in to about 4 turns out it runs best with the air screw about 1 1/2 turns out and fuel about 2 turns. But the choke still must be on. When I disabled it I took everything apart that could come off then soaked it. The air filter is like new and I replaced the o rings for the carb to intakes and can't find any other vacuum leaks.

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I had a similar problem with an older version of the same bike.. in the end it was either bad gas or sediment in the tank.. the only solution I could find was clean the tank and carb repeatedly. My guess is u have a similar problem, but it would also help to know what your spark plug is looking like after running the bike.

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I had some surgeries and my bike sat in garage for about 2 years.   I drained the gas and flushed the tank, opened bottom of float bowl and carb sprayed it, clean. Then ran another 1/2 gallon of fresh gas through tank and hoses.  IT STILL CLOGGED the pilot jet.  Why? because the gas got gummy, and sticks to the inside of every thing with a thin coat of crap.  Like Spencersmith89 said, flush the heck out of the tank, even use carb cleaner on it.  You should only need ONE more carb cleaning to end the problem at that time.  Make sure you remove and clean your pilot jet, and air fuel mixture adjusters and clean them good.  No need to run additives in the gas, it probably will cause more problems than it will fix.  Next time I let my bike stand more than a few months, I will drain the tank first, run carb dry, then park it.  If you have wide open throttle  miss fire, the main jet will need cleaning too.

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To add to what slip said only let your tank sit dry if its plastic.. I've seen way to many bikes n tractors with metal tanks develop rust inside due to condensation. Even with a plastic tank make sure u rinse it with gas after sitting for a long time and dispose of the gas u use to rinse to remove any condensation or dust accumulation in the tank.

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Two carb rebuilds the second one spent a lot of time in chemdip then cleaned blown out with air then carb cleaner and blown out again then gas dumped and tank rinsed with gas and dumped runs good now but idles fast even with air screw out alot

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hi, seems like you are doing the right things, with cleaning out the fuel system.   As for fast Idle, the further out the air fuel mixture screw is, the higher the idle will be if you turn it OUT (richer) too far, things go backwards.   I have my 22 mm mikuni copy carb, air/fuel screw set at 2.5 turns out from dead stop.  It also works well at 2 turns out.  less than two turns and you get the backfire and rough idle again along with some hesitation, especially when cold.    Set it at 2.5 turns out.  You might need to clean everything out, ONE more time, after about 2 hours of running it, some crud will get stuck in pilot jet again, causing idle problems and low speed problems, if so, clean it all again.   IF after three complete clean outs it still messes up..  then CRAP... it is not a good sign. Stuff is still coming from your gas tank, down the fuel lines and into the carb.  This is normal, and will go away the more you ride with no problems the better the fuel system is getting.  Be very suspicious of the fuel tank as the cause.  If you are going to store your bike more than two or three months, put fuel stabilizer in the tank.   Of course always use highest octane gas and freshest.

note: I rinsed my gas tank with fresh gas three times and it still sent crud down to the carb.   Use a carb cleaner in the gas tank, like three times.   Good luck.  and in future, start that bike once every 40 days or so, no longer.   OH another tip, if you ride only once a month or less, turn off the gas supply to carb, let engine run itself dry, then park it.

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