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Main Area => General GS500 Discussion => Topic started by: bobthebiker on October 26, 2007, 08:18:28 PM

Title: running lean at idle and around 4k rpm
Post by: bobthebiker on October 26, 2007, 08:18:28 PM
Ok, so me, being the freakin GENIUS I am, I decided today to try and make my reasonably good running GS run a little better,  and now, I'm running so lean it feels like the whole choke is on kind of deal, but its not.    can someone tell me, will rejetting the carbs to a slightly larger main jet help me at all?

my problem is mainly that, when I start it, it'll idle just fine for a second, then as if I magically manage somehow to put the choke on, it revs up to around 4k rpm without me helping it at all.   does this all the freakin time too.   I looked earlier for air leaks, found none, and have no idea why the hell this bike would do this, besides something stupid like the lean factory jet size.

Title: Re: running lean at idle and around 4k rpm
Post by: DrtRydr23 on October 26, 2007, 09:57:10 PM
What did you do to try to make it run better?
Title: Re: running lean at idle and around 4k rpm
Post by: bobthebiker on October 26, 2007, 10:15:43 PM
all I did was richen the mixture with the screws on the bottom, being that I know its worked well on other bikes, I thought it would help here. apparently not.
Title: Re: running lean at idle and around 4k rpm
Post by: DrtRydr23 on October 27, 2007, 04:25:06 PM
Gimme some more info on your setup.  Current carb settings, air filter, and exhaust will help.  I would turn the screw back in to the old setting before making any changes to get it back to status quo.
Title: Re: running lean at idle and around 4k rpm
Post by: jwjulian on December 29, 2009, 09:31:50 PM
are you sure you didn't turn the idle adjustment screw?
Title: Re: running lean at idle and around 4k rpm
Post by: black and silver twin on December 30, 2009, 11:49:24 PM
Quote from: jwjulian on December 29, 2009, 09:31:50 PM
are you sure you didn't turn the idle adjustment screw?

word, the mixture screws are small brass flathead screws on the bottom of the carbs in front of the float bowls, there is one on each carb.
If your sure you only adjusted the mix screws then how far did you go, most people find between 2.5 and 3.75 turns out perfect. also if you did adjust the mix screws correctly then the idle rpm would increase with the same idle adjustment. make sure you adjusted the mix screws correcly, check again for vacuum leaks then adjust idle with the idle adjustment knob. there is one idle knob, its between the carbs and sticks down so it can be turned by hand. idle should be 1100-1200rpm
Title: Re: running lean at idle and around 4k rpm
Post by: The Buddha on December 31, 2009, 07:35:19 AM
Quote from: bobthebiker on October 26, 2007, 08:18:28 PM
Ok, so me, being the freakin GENIUS I am, I decided today to try and make my reasonably good running GS run a little better,  and now, I'm running so lean it feels like the whole choke is on kind of deal, but its not.    can someone tell me, will rejetting the carbs to a slightly larger main jet help me at all?

my problem is mainly that, when I start it, it'll idle just fine for a second, then as if I magically manage somehow to put the choke on, it revs up to around 4k rpm without me helping it at all.   does this all the freakin time too.   I looked earlier for air leaks, found none, and have no idea why the hell this bike would do this, besides something stupid like the lean factory jet size.



You're idling at 4K without choke ?
Yea did you fiddle with idle screw instead of air screw ... good Question.
Cool.
Buddha.