Author Topic: quick quest k2  (Read 588 times)

Offline El__burro

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quick quest k2
« 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

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Offline Trigger

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Re: quick quest k2
« Reply #1 on: July 04, 2018, 07:05:44 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

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

Offline El__burro

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Re: quick quest k2
« Reply #2 on: July 04, 2018, 02:53:14 PM »
Thanks,
 still I need to unscrew it all to have a blue explosion (with colortune).
.. so turn in to lean it?
el__burro

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Offline JamesH

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Re: quick quest k2
« Reply #3 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?

Offline K2-K6

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Re: quick quest k2
« Reply #4 on: July 04, 2018, 07:14:06 PM »
You should be getting a change in rpm as you adjust an individual air screw,  it'll accelerate or decrease that cylinder which you can hear change.  If not,  you'd suspect the air or fuel circuit for that carb was impaired and needed cleaning.

http://www.iwt.com.au/mikunicarb.htm this may help in understanding what is happening.

Offline JamesH

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quick quest k2
« Reply #5 on: July 04, 2018, 07:22:39 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?
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..

Offline JamesH

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Re: quick quest k2
« Reply #6 on: July 04, 2018, 07:23:03 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?
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..

Offline petermigreen

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Re: quick quest k2
« Reply #7 on: July 05, 2018, 09:57:17 PM »
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

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

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."

« Last Edit: July 05, 2018, 10:03:06 PM by petermigreen »

 

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