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Main Area => General GS500 Discussion => Topic started by: spdracer75 on August 03, 2004, 01:16:25 PM

Title: Anyone have a pic of the tank petcock set to "on&am
Post by: spdracer75 on August 03, 2004, 01:16:25 PM
I think my tank mounted petcock might not be completely open.

At around 80% throttle, If I got to WOT the bike stumbles a little, like it's starved for gas.

I have about 3/4 of a tank, my lines are nice and clear, with no noticeable kinks.

Thanks
Title: Anyone have a pic of the tank petcock set to "on"
Post by: Kerry on August 03, 2004, 01:34:29 PM
Vertical is ON.  (Like in photo below.)

Horizontal -- in either direction -- is OFF.

Anywhere in between vertical and horizontal is PARTLY ON.

(http://www.bbburma.net/MiscFotos/100_1485_TankPetcockInONPosition.jpg)
Title: Re: Anyone have a pic of the tank petcock set to "o
Post by: Kerry on August 03, 2004, 01:40:22 PM
Quote from: spdracer75At around 80% throttle, If I got to WOT the bike stumbles a little, like it's starved for gas.
This has happened on both my (now richard's) '96  and my '99.  But it's pretty instantaneous, right?  You crank the throttle from 80% to WOT and it stumbles right now.  That would not be a fuel starvation problem.

There's probably still plenty of fuel in your lines and float bowls; it takes a little while at WOT for the consumption to "get ahead" of the supply and empty the supply hose.

I've been thinking that this is an issue with jetting or mixture screw settings or the air supply, but since my carbs are still stock I have been loathe to goof with 'em.
Title: Anyone have a pic of the tank petcock set to "on"
Post by: spdracer75 on August 03, 2004, 02:29:59 PM
Kerry,


well, I did have that issue thinking 134 mains were a bit small for my GS.

Thanks for the tip.  As for air cleaner, my K&N is in the air box, it's not an open element "pod?" type.

Once I get this key issue taken care of I may take it to a shop for performance tuning.
Title: Anyone have a pic of the tank petcock set to "on"
Post by: MarkusN on August 04, 2004, 05:47:45 AM
Actually stumbling when opening up from 80% to 100% is an indication of rich mixture. I had that problem when my float height was way off and the fuel level in the float chamber was almost half an inch high.