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quick quest k2

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JamesH:

--- Quote from: Jamesh_sussex on July 04, 2018, 04:00:45 PM ---If you're running standard K2 carbs (round top type) your idle air mixture screws should be on the airbox (inlet) side of the carb assembly (i.e. in front of the slides). This screw adjusts the idle air mixture (i.e. the amount of idle air mixed with the pilot fuel mixture). So, screwing in (clockwise) reduces the amount of pilot air (richer) and screwing out (counter-clockwise) increases the amount of idle air (leaner). At least that's my take on it...

Stock screw position I work to is 1 - 1 1/4 turns out for the idle air screws.

If you want to adjust the overall lean/rich mixture right up to WOT then you need to adjust the main needle clip position. A lower clip position will give a richer mixture, a higher clip position a leaner mixture.

Make sense?

--- End quote ---
I’m actually talking complete bollox here I think. Trigger - you are right. The screw position controls the amount of aerated ‘vacuum’ air available to the pilot circuit, so increasing the amount of air increases the pilot fuel mixture. So opening the screw does result in a richer pilot fuel mixture..

JamesH:

--- Quote from: Jamesh_sussex on July 04, 2018, 07:22:39 PM ---
--- Quote from: Jamesh_sussex on July 04, 2018, 04:00:45 PM ---If you're running standard K2 carbs (round top type) your idle air mixture screws should be on the airbox (inlet) side of the carb assembly (i.e. in front of the slides). This screw adjusts the idle air mixture (i.e. the amount of idle air mixed with the pilot fuel mixture). So, screwing in (clockwise) reduces the amount of pilot air (richer) and screwing out (counter-clockwise) increases the amount of idle air (leaner). At least that's my take on it...

Stock screw position I work to is 1 - 1 1/4 turns out for the idle air screws.

If you want to adjust the overall lean/rich mixture right up to WOT then you need to adjust the main needle clip position. A lower clip position will give a richer mixture, a higher clip position a leaner mixture.

Make sense?

--- End quote ---
I’m actually talking complete bollox here I think. Trigger - you are right. The screw position controls the amount of aerated ‘vacuum’ air available to the pilot circuit, so increasing the amount of air increases the pilot fuel mixture. So opening the screw does result in a richer pilot fuel mixture..

--- End quote ---

petermigreen:

--- Quote from: Trigger on July 04, 2018, 07:05:44 AM ---
--- Quote from: El__burro on July 04, 2018, 12:05:07 AM ---My spark plug is very carbon fouled, my air screw mix almost all out..
should i drop or rise the needle in the carburettor?
Thank you
el__burro

Sent from my SM-G935F using Tapatalk

--- End quote ---

For more air to the mix, you screw it in  ;) Not out ???

--- End quote ---

This has been bothering me.
Taken from the carb tuning guide on sohc4.net

"What happens when I turn the airscrew out - richer or leaner?
If your airscrew is on airbox side of carb, turning out will lean mixture; opposite if airscrew is on engine side of carb."

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