Del 20/20 carb problem

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Soulstylist
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Running a 20/20 dellorto carb, symptoms are , it is running no problem at 1/4 revs upwards and will tick over from cold with choke out,
but when choke is in and as soon as the throttle is dropped to try and tick over, it conks out..
Can someone give me an idea of the actual job of the pilot jet in conjunction with the mainjet and what they may think the problem is.. (pilot jet blocked or goosed?)
Thanks for any input, help or info..
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cgt75b
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Have you tried adjusting the tick over screw ? The big one that sticks out of the carb cover lid ?
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Soulstylist
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Yeah I did all that, the carb was running great, but it's as if it's running out of petrol at lower revs (tick over and just above), that's why I'm trying to find out the actual working operation of both jets, does the smaller jet run the carb at smaller revs e.g. just a tick over and slightly higher, then does the main jet cut in as the revs open up ?
Cheers
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Shaunbond
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Chris in Margate
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Why not remove it, strip it and clean it through thoroughly. Blow the jets out and reassemble. About an hour to do it all. If you are unsure take pictures on your mobile at each stage.
Does sound like pilot jet circuit is the problem.
mick1
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As above ^

Check your fuel flow from the tank as well .......could be a blockage that clears when revved up. Also check fuel filters.
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