Date: 10-11-25  Time: 07:45 am

Author Topic: Air screws - in or out to lean  (Read 1510 times)

Captain Haddock

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Air screws - in or out to lean
« on: 05 July 2019, 02:39:39 pm »
Can someone please remind me which way the air screws go on a though to lean off a touch, carbs are ivanised but after standing I've just blown the passages and jets through to cure a misfire but still got a tiny splutter just at pulling away speed, carbs are balanced and idles lovely I think it's just a touch rich.Currently 4 turns out but note ivanising instructions recommend 4.5-5 turns out, is that leaner or richer? Must find a small child to get their hands in to adjust and try.Otherwise runs superbly and pulls like a train all the way to "a tad over 70 officer".

coffee

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Re: Air screws - in or out to lean
« Reply #1 on: 05 July 2019, 10:22:30 pm »
I would have thought screwing in would be leaning the mixture and out to richen,not 100% though just seems obvious that way.

Captain Haddock

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Re: Air screws - in or out to lean
« Reply #2 on: 07 July 2019, 01:01:41 am »
Anyone with more than a guess?

Trebus

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Re: Air screws - in or out to lean
« Reply #3 on: 07 July 2019, 08:37:43 am »
They are tapered air screws, turning out (anti-clockwise) to increase air therefore leaner mixture.

Captain Haddock

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Re: Air screws - in or out to lean
« Reply #4 on: 07 July 2019, 10:01:25 am »
Thanks for that, confirms the way I was thinking so will give it a go, need smaller hands though.....

Falcon 269

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Re: Air screws - in or out to lean
« Reply #5 on: 08 July 2019, 08:06:35 am »
The mixture screws control fuel flow on the Fazer 1000, so out to richen, in to lean. :)

The paragraph titled 'Drill Out Mixture Screw Plugs' here is accurate and informative.  Explains the difference in mixture screw settings depending on whether the carbs have one or two of the pilot circuit bypass holes enlarged.

http://www.cartestsoftware.com/fz1/jetkitinstallation.html

Captain Haddock

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Re: Air screws - in or out to lean
« Reply #6 on: 01 August 2019, 06:38:34 pm »
The mixture screws control fuel flow on the Fazer 1000, so out to richen, in to lean. :)

The paragraph titled 'Drill Out Mixture Screw Plugs' here is accurate and informative.  Explains the difference in mixture screw settings depending on whether the carbs have one or two of the pilot circuit bypass holes enlarged.

http://www.cartestsoftware.com/fz1/jetkitinstallation.html
Thanks for that, now I'm back off holiday I should get around to this hopefully.