GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: Cusimano on June 17, 2008, 06:28:44 PM

Title: please help carb question
Post by: Cusimano on June 17, 2008, 06:28:44 PM
my gs has a stock exhuast, pod kn, and two #4 washers and one down on the front sproket. i recently broke out my bike after winterizing it. and when i ride at 50mph and around 5-7krpm i have what feels to be a fuel starvation issue. usaully when i would feel that its when im on a highway at 65mph and for a period of time, though when i switch over from 'on' to 'pri' fuel petcock it then go away. i tore down the carbs cleaned it out made sure that there wasnt any clogged jets. redid all the o-rings and gaskets ( adjusted the bowl float last year so i didnt think i need to check that again). when i check the air/fuel screw one side was at 6 out and the other was at 3 out, so i corrected that and made them both 3 turns out. went for another ride. and the hesitation is worse at a half throttle. if i give it a little gas its ok, if i open it completly up its fine, BUT at half throttle it kicks and bucks with horrible hesitation.  i pulled the plugs and they were new when i first went out for this ride and there were tan, so i cant figure out what the issue is at half throttle.  :dunno_white:
Title: Re: please help carb question
Post by: beRto on June 17, 2008, 06:41:48 PM
Are you sure it's a carb problem. Fuel starvation is often caused by a bad frame-mounted petcock. This sounds especially likely when you consider that switching to PRI made the problem go away.

Search for fuel starvation and you will find dozens of related threads.

The wiki also has some useful info:
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Petcock

Title: Re: please help carb question
Post by: Cusimano on June 17, 2008, 06:49:38 PM
im not sure if its a carb problem then again i have no idea what it could be then. the petcock is newer, and the problem would go awhile on highway rides, it doesnt fix this problem with the half throttle riding. nothing helps the problem.
Title: Re: please help carb question
Post by: ben2go on June 17, 2008, 09:04:40 PM
Have you tried riding on PRIme?If it clears up on PRIme see these threads to fix the petcock.


I do this mod.PM me for details.
http://gstwins.com/gsboard/index.php?topic=19363.0

This is a cheap nonvacuum alternative.
http://gstwins.com/gsboard/index.php?topic=36958.0
Title: Re: please help carb question
Post by: Cusimano on June 18, 2008, 09:10:05 AM
yea i have tried riding on prime but it doesnt do anything.
Title: Re: please help carb question
Post by: ben2go on June 18, 2008, 09:35:42 AM
Sounds like a main jet is clogged.Clean barbs.
Title: Re: please help carb question
Post by: beRto on June 18, 2008, 09:42:36 AM
Quote from: Cusimano on June 18, 2008, 09:10:05 AM
yea i have tried riding on prime but it doesnt do anything.

:icon_confused: Your first post said the problem went away when you switched to PRI?

Quote from: Cusimano on June 17, 2008, 06:28:44 PM
when i ride at 50mph and around 5-7krpm i have what feels to be a fuel starvation issue. usaully when i would feel that its when im on a highway at 65mph and for a period of time, though when i switch over from 'on' to 'pri' fuel petcock it then go away.
Title: Re: please help carb question
Post by: Cusimano on June 18, 2008, 10:16:35 AM
sorry if i wrote it kinda confusing, the issue im having now is just riding at portial throttle, after fully cleaning the carbs. i was just stating that i use to have an issue with i highway rides that were corrected by turning it to prime. but the issue im having now doesnt clear up when turning it to prime.