Pilot screw adjustment

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The Novice
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Bike owned: NC23 NC30 CRM250
Location: West Midlands

Pilot screw adjustment

Post by The Novice » Thu Mar 31, 2011 4:36 pm

I think I understand how to adjust the mixture, ie screw in pilot screw till it splutters and is dying, screw out till you get to point where revs rise to a maximum. go past that and it will start to die again, screw back in till its at the highest idle. Then adjust the idle screw to suit.

My q is, when adjusting as there are 4 carbs and 4 pilot screws!! , do you
1)have to do 1 pilot screw, then just adjust all the others to whatever its screwed out to?
2) adjust all 4 pilot screws individually? ie 1 by 1
3) adjust 4 pilot screws but all at the same time, if that makes sense. ie incremental adjustments to all pilots.

when thats done, then you balance the carbs dont you.

Just trying to get it sorted in my head before i have a go.

Wozza
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Re: Pilot screw adjustment

Post by Wozza » Fri Apr 01, 2011 5:59 pm

For that method I think I would try using 2), adjusting by 1/4 turn each time - if it is difficult due to the revs changing by too small an amount I would use 3). Ideally you want all the pilot screws to be on the same setting - don't forget the pilot jet still supplies a small amount of fuel all the way up the rev range, so has a small effect on needle heights / main jet sizes. Also, balance the carbs first - this determines (relative) airflow which determines fuel flow.

I use the throttle-blip method, adjusting as in 3), but the method you describe is a good one.

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