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Main Area => General GS500 Discussion => Topic started by: smittybuilt92 on August 01, 2013, 08:17:10 PM

Title: air or fuel mixture screw?
Post by: smittybuilt92 on August 01, 2013, 08:17:10 PM
This may be a dumb question but on my 97 gs500e is the mixture screw on the bottom of the carbs a fuel or air mixture screw?
Title: Re: air or fuel mixture screw?
Post by: RossLH on August 01, 2013, 08:26:38 PM
The screw between the carbs is the idle adjuster. The mixture screws are located on the bottom of each carb.
Title: Re: air or fuel mixture screw?
Post by: DrtRydr23 on August 02, 2013, 04:39:18 PM
The idle adjustment knob just opens/closes the butterfly valves to change the idle rpms I think.  As I understand it, the mixture screws at the bottom of each carb are air screws. 
Title: Re: air or fuel mixture screw?
Post by: adidasguy on August 02, 2013, 09:27:32 PM
The idle screw is simply a throttle stop. All it does is keep the throttle from closing as much or allows it to close more. It doesn't adjust anything.
Title: Re: air or fuel mixture screw?
Post by: DrtRydr23 on August 03, 2013, 07:04:44 AM
Quote from: adidasguy on August 02, 2013, 09:27:32 PM
The idle screw is simply a throttle stop. All it does is keep the throttle from closing as much or allows it to close more. It doesn't adjust anything.

Technically, it does change the size of the throttle opening at idle.  So it actually adjusts two things:  the size of the gap between the butterfly valves and the carb body, and as a result the rpm's at idle.  Just sayin'.
Title: Re: air or fuel mixture screw?
Post by: adidasguy on August 03, 2013, 02:20:42 PM
Quote from: DrtRydr23 on August 03, 2013, 07:04:44 AM
Quote from: adidasguy on August 02, 2013, 09:27:32 PM
The idle screw is simply a throttle stop. All it does is keep the throttle from closing as much or allows it to close more. It doesn't adjust anything.

Technically, it does change the size of the throttle opening at idle.  So it actually adjusts two things:  the size of the gap between the butterfly valves and the carb body, and as a result the rpm's at idle.  Just sayin'.
Look carefully at our carbs. The idle screw is just a throttle stop. Nothing more. Located where the throttle cable comes in, between the carbs. It is the same as holding the throttle a little more open or not - i.e. twisting the throttle a little - does the same thing.

Other carbs on cars or different bikes might be different.
Title: Re: air or fuel mixture screw?
Post by: smittybuilt92 on August 06, 2013, 04:55:37 PM
Thank you all. I just wanted to know if the mixure screw was a air or fuel mixture screw. Just having teoubles after warm up thinkin its these screws
Title: Re: air or fuel mixture screw?
Post by: Big Rich on August 06, 2013, 05:26:27 PM
Um....they are air / fuel mixture screws. The further they are screwed in, they mix less gas with the air. Screw them out and they mix more gas with the air.

What makes you think it might be the mixture screws that need adjusted?
Title: Re: air or fuel mixture screw?
Post by: smittybuilt92 on August 06, 2013, 06:01:34 PM
Ive got a hunch. Everyone says valve ckearence but they are all in spec an the bike only has 1700 miles on it. The bike studders an eventually dies after warm up
Title: Re: air or fuel mixture screw?
Post by: smittybuilt92 on August 06, 2013, 06:53:56 PM
My hunch was wrong.. I just disconeced the fuel.line that feeds the carb from petcock. Ran the bike an kept adding fuel never acted up once. So tue new problem.is either a dirty petcock or pinched fuel line .. Thats my guess at least.