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Main Area => General GS500 Discussion => Topic started by: weaselnoze on April 19, 2011, 02:04:22 PM

Title: Tank/Frame Petcock and carb question
Post by: weaselnoze on April 19, 2011, 02:04:22 PM
I took my carbs apart for the third time to adjust floats, put it all back together, and now i'm not getting any gas to the bowls.  I opened the drain screws and nothing came out!

1) on the tank petcock, I'm confused on the position of the valve.  Is all the way one way ON and all the way the other direction OFF? Or is it OFF>ON>OFF? 

2) if the diaphram was bad on the frame mounted petcock, what would happen? 

3) Clymer says 13.6 - 15.6mm for the floats.  If it measured >15.6mm the valve would never shut causing the bowls to over flow, right? if it were <13.6mm then would they be plugged and no fuel will go into the bowl?  Do i have that right or am i backwards?

Title: Re: Tank/Frame Petcock and carb question
Post by: Yuri. on April 19, 2011, 02:07:04 PM
Can help with the first, it's off-on-off
Title: Re: Tank/Frame Petcock and carb question
Post by: skirecs on April 19, 2011, 02:23:44 PM
id bet you turned the tank petcock too far
Title: Re: Tank/Frame Petcock and carb question
Post by: weaselnoze on April 19, 2011, 02:56:54 PM
SONOFA...

i knew it had to be off>on>off.  I PULLED THE STUPID CARBS 3 TIMES BECAUSE OF THIS.

after the initial cleaning it ran fine but the float was stuck.  then i pulled em, adjusted, then it started up fine until ran out of gas all because it was 'off'. 
Title: Re: Tank/Frame Petcock and carb question
Post by: weaselnoze on April 19, 2011, 05:52:01 PM
well i tried turning the tank petcock to on, still no fuel in the carb bowls.  i'll have to look closer tomorrow..
Title: Re: Tank/Frame Petcock and carb question
Post by: werase643 on April 19, 2011, 06:14:45 PM
have you considered checking the flow with the tank NOT connected so you can figure it out
if you want to check flow through the petcock
turn to prime and if you want to check the on position....suck on the vac hose to check flow
Title: Re: Tank/Frame Petcock and carb question
Post by: weaselnoze on April 19, 2011, 07:54:02 PM
To be clear, petcock in PRIME,suck on vac hose coming from top of carb And what will happen if its supposed to be working right? Gas should come out the vacuum tube?
Title: Re: Tank/Frame Petcock and carb question
Post by: MrTwinkle on April 20, 2011, 03:11:51 AM
No. With the petcock in PRIME the gas should flow from the tank to the carbs without you sucking on anything. With the petcock in the ON position you will have to suck on the vacuum hose and gas will flow =)
Title: Re: Tank/Frame Petcock and carb question
Post by: mass-hole on April 20, 2011, 09:56:53 AM
Quote from: MrTwinkle on April 20, 2011, 03:11:51 AM
No. With the petcock in PRIME the gas should flow from the tank to the carbs without you sucking on anything. With the petcock in the ON position you will have to suck on the vacuum hose and gas will flow =)

This is turning into a great motorcycle porno, with all this talk of petcocks and hose sucking.
Title: Re: Tank/Frame Petcock and carb question
Post by: plewis51 on April 20, 2011, 10:59:17 AM
Remember, to remove the hose from your mouth after initial suck. Unless you like gurgling gas.
Title: Re: Tank/Frame Petcock and carb question
Post by: gsJack on April 20, 2011, 11:18:02 AM
Quote from: weaselnoze on April 19, 2011, 02:04:22 PM
1) on the tank petcock, I'm confused on the position of the valve.  Is all the way one way ON and all the way the other direction OFF? Or is it OFF>ON>OFF? 

For the tank petcock turn the screwdriver slot horizontal to turn off and vertical to turn on.  Just picture the screwdriver slot blocking flow or allowing it to pass.  And with the frame selector chicken if it's turned to PRI gas will flow thru it freely if the tank petcock is on.
Title: Re: Tank/Frame Petcock and carb question
Post by: burning1 on April 20, 2011, 11:20:42 AM
At most race weekends, I forget to turn my petcock on in the morning. Always end up wondering why the bike dies/runs funny.