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Main Area => General GS500 Discussion => Topic started by: intergalactic on June 28, 2009, 06:27:26 PM

Title: New jets and 08 petcock- MUCH better
Post by: intergalactic on June 28, 2009, 06:27:26 PM
So I have been grumpy about mt GS- it runs like crap on stock jets. I knew the carbs had gotten a LITTLE bit of rust in them when I wasn't careful with the fuel filter install, as a I have a tank with a small rust spot. And I was running stock (37.5/122.5) jets with no needle washers.

So today I cleaned out the carbs, changed to 40/125 jets and added two washers to the needles, per Buddha's kit. Changed the float seat o-rings and the ones under the top cap. I had already done the float assembly o-rings when I cleaned the float bowls and jets a month ago.

Even freshly cleaned with stock jets, the GS was sluggish until it was really hot. Like highway hot.  40MPH putting let it cool off until the throttle developed a flat spot.  But with the new jets and washers on the needles, it runs quite well when cool. No dangerous bogging down leaving the apartment complex. It was raining tonight and 70F/19C outside. Throttle response was good out of the box with 2 turns on the idle air screws, no fine adjustments made. I *suspect* it is a bit rich when fully warm, but we will see. I could use a new air filter soon, I think anyways. So I might be choked out on the top end now with a dirty foam universal fit filter.

No matter what, this is the best the bike has run since I bought it.



Also, I installed a 08 petcock. the fittings are larger than the 89-00 petcock. So I bought '08 hoses from suzuki and they fit perfectly. The petcock itself needs to be offset from the stock location about an inch/25mm.  Priming seemed weak on a completely dry system, but the bike started fine first try.

Title: Re: New jets and 08 petcock- MUCH better
Post by: intergalactic on June 30, 2009, 01:52:39 PM
Petcock fixed the fuel starving so far, and the throttle response is SOOOOO much better. I don't have to downshift all the time now.
Title: Re: New jets and 08 petcock- MUCH better
Post by: jonny5neal on July 31, 2009, 09:01:31 AM
I own a 99 gs500 and i have the petcock fuel starvation issues at high speeds.  did you make a bracket for the new petcock to fasten to?
Do you have pictures?

Thanks,
J5
Title: Re: New jets and 08 petcock- MUCH better
Post by: intergalactic on July 31, 2009, 09:10:02 AM
Hey, I still have issues. Not sure what it is. Although it seems that the position of the petcock being only just above the carb doesn't help.

I haven't made a bracket yet.  I have it hanging by some wire :)

Quote from: jonny5neal on July 31, 2009, 09:01:31 AM
I own a 99 gs500 and i have the petcock fuel starvation issues at high speeds.  did you make a bracket for the new petcock to fasten to?
Do you have pictures?

Thanks,
J5