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Main Area => General GS500 Discussion => Topic started by: Bulwark on November 22, 2006, 01:10:30 PM

Title: I find it odd that my new GS doesnt have a fuel off position.
Post by: Bulwark on November 22, 2006, 01:10:30 PM
It has On, Res, and Prime.  Odd that there is no off.
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: RVertigo on November 22, 2006, 01:13:34 PM
Most newer bikes don't...

The vacuum pulls the gas in, so you don't need to turn the petcock to OFF...

Setting it to "Pri" will let it keep flowing until it floods and spills all over the floor.



If you want to shut off the gas from the tank, there's another petcock on the tank...  It has ON and OFF.
Title: Re: I find it odd that my new GS doesnt have a fuel off position.
Post by: scratch on November 22, 2006, 01:14:27 PM
You are correct.  That is the fuel selector switch.  It will act as an off, when in the On and Res. positions due to the fact that vacuum is needed to flow fuel past the diaphragm.

The true "off" valve is under the tank, mounted to the tank.
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: FearedGS500 on November 22, 2006, 01:28:05 PM
and that i know of you have to take the two bolts out and left the tank up to get to it ..unless you can dget to it front underneath  :dunno_white:
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: dgyver on November 22, 2006, 01:49:39 PM
Quote from: RVertigo on November 22, 2006, 01:13:34 PM
....
Setting it to "Pri" will let it keep flowing until it floods and spills all over the floor.
....

This is only true if your float needles do not seat correctly.


btw....you can eliminate the vacuum part of the valve and turn it into a On/Off/Reserve valve, but permanent modifications are required.
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: RVertigo on November 22, 2006, 02:59:08 PM
Quote from: dgyver on November 22, 2006, 01:49:39 PMThis is only true if your float needles do not seat correctly.
Well, either I have a problem or I flooded it some other way....   :icon_confused:
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: gsbarry on November 23, 2006, 07:44:32 AM
Not to sure why you would be concerned with having an "off" setting on your outer petcock. The bike should beable to sit , store whatever with the petcock in the "on" position without a problem. Unless ur taking the tank off. Which in that case you will beable to reach the inner petcock, than you shouldnt need an off position on the outter...

And besides i think because there are 3 settings already, "On", "Off" and "Res" there is no possibility to get it to have a closed "off" position. You would need to eliminate the "Res".... i think.... and who doesnt want reserve. I know it saved me a few times.

~Barry~
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: dgyver on November 23, 2006, 09:01:59 AM
The 3 positions are On, Reserve, and Prime. Modifiing the valve will eliminate Prime and add Off. One problem with the valve is that it operates by vacuum of the left carb. So any problems with the left side of the motor affects both sides. There is a rubber flapper type check valve in the vacuum circuit and the one I removed turned into a gummy mess. It had sealed the vacuum port closed. This is probably the main problem that makes people have to run in Prime. Running in Prime eliminates these problems but is not a perfect solution. The orifice for the Prime circuit is about an 1/8" where the On and Reserve are at least 3/16".

Here is the link to the modification:
http://gstwins.com/gsboard/index.php?topic=19363.0
Title: Re: I find it off that my new GS doesnt have a fuel off position.
Post by: gsbarry on November 24, 2006, 02:55:04 PM
ooops i meant "prime" not "off"....
Title: Re: I find it odd that my new GS doesnt have a fuel off position.
Post by: baco99 on November 27, 2006, 12:23:04 PM
i've left it in PRIME without spilling over.  i usually leave it ON, tho.