AIR SCREW ADJUSTMENT

FLASHLIGHTBOY · 08-30-2009, 01:38 AM

On the 110 cc atv.. there is a air screw that you can adjust to make it run better... what is the problem if you turn this and it does not have any effect on the running.. I have it turned in almost all the way.. and if I unscrew it the normal 2 turns .. it will not run properly??? I took the carb apart and check the orifices they are not plugged.. any ideas ??

Weldangrind · 08-30-2009, 02:33 AM

I'm not exactly sure of what you're saying, but the air / fuel screw is only for idle. As soon as you open the throttle, everything changes.

Ideally, the air / fuel screw should be adjusted so that there is little to no bog upon opening the throttle quickly, and it should be adjusted for maximum RPM at a given idle setting (tough to do without a tach, so just play with it). Be gentle when turning the screw all the way in; you don't want to damage the seat.

TurboT · 08-30-2009, 02:39 AM

I have found quite simply this screw makes virtually no difference to the way my machines run at all, at any setting, unless it falls out then there's a problem. (Yes one of them rattled itself out, now they have tape over them)

I've turned it in, turned it out, set it halfway and then just threw up my hands and said "bleep it" .. The choke levers have way more effect on proper running than that screw.

Reveeen · 08-30-2009, 01:12 PM

what is the problem if you turn this and it does not have any effect on the running

The idle air/fuel screw is for adjusting your mixture at an idle. You want to adjust it for the maximum RPM, then richen it a bit to allow for smooth transition into a throttle situation.

It does not work when:
1) you don't have intake vacuum (caused by:vacuum leak at carb, or manifold, tight intake valve, main jet open/missing (throttle cable too tight, idle adjusted too high, missing clip on needle)
2) carb flooding (float set too high)
3) defective/dirty carb
4) timing right out to lunch (it has to be way off)

FLASHLIGHTBOY · 08-31-2009, 12:59 AM

THANKS FOR THE HELP.. I will check these things

08-30-2009, 01:38 AM	#1
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	AIR SCREW ADJUSTMENT On the 110 cc atv.. there is a air screw that you can adjust to make it run better... what is the problem if you turn this and it does not have any effect on the running.. I have it turned in almost all the way.. and if I unscrew it the normal 2 turns .. it will not run properly??? I took the carb apart and check the orifices they are not plugged.. any ideas ??
	0

08-30-2009, 02:33 AM	#2
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	I'm not exactly sure of what you're saying, but the air / fuel screw is only for idle. As soon as you open the throttle, everything changes. Ideally, the air / fuel screw should be adjusted so that there is little to no bog upon opening the throttle quickly, and it should be adjusted for maximum RPM at a given idle setting (tough to do without a tach, so just play with it). Be gentle when turning the screw all the way in; you don't want to damage the seat. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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08-31-2009, 12:59 AM	#5
FLASHLIGHTBOY Join Date: May 2009 Location: SASKATOON Posts: 1,161	AIR SCREW SETTING THANKS FOR THE HELP.. I will check these things
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08-30-2009, 02:39 AM	#3
TurboT Join Date: Sep 2008 Location: Surrey, B.C., Canada Posts: 2,185	I have found quite simply this screw makes virtually no difference to the way my machines run at all, at any setting, unless it falls out then there's a problem. (Yes one of them rattled itself out, now they have tape over them) I've turned it in, turned it out, set it halfway and then just threw up my hands and said "bleep it" .. The choke levers have way more effect on proper running than that screw.
	0

08-30-2009, 01:12 PM	#4
Reveeen Join Date: Jun 2009 Location: orbital platform Posts: 741	what is the problem if you turn this and it does not have any effect on the running The idle air/fuel screw is for adjusting your mixture at an idle. You want to adjust it for the maximum RPM, then richen it a bit to allow for smooth transition into a throttle situation. It does not work when: 1) you don't have intake vacuum (caused by:vacuum leak at carb, or manifold, tight intake valve, main jet open/missing (throttle cable too tight, idle adjusted too high, missing clip on needle) 2) carb flooding (float set too high) 3) defective/dirty carb 4) timing right out to lunch (it has to be way off)
	0