Since I've been messing with my carbs, changing the diaphragms, cleaning them, I have been getting a very odd fuel problem. My bike uses about three gallons of gas and quits. The reserve doesnt work (never did) - but there is still plenty of gas, and I'm still getting the same fuel mileage.

I'm getting about 120 miles before this happens, before the problem I was getting about 160.

Argghh

Before you messed with your carbs did you happen to check your gas level at 160 miles?  Is it the same level that you are at at 120 miles now?

Before it would take about 3.3 gallons to fill up. Now it takes about 3.

Odd

Why doesn't the reserve work?

HI Jon,try switching the two fuel lines at the tap,my gs didn`t have res` when i first got it and that was the problem.

Hmm thats interesting, is there a way to check the lines without switching em? I assume you mean the ones going to the petcock?

Here they are for all years, gotta put it on the Wiki one of these days.  The pic there is for the original 89-00 models only.

http://img.photobucket.com/albums/v443/jcp8832/GS500fuelcocks.jpg

Thanks! I'm going to check that asap.

Quote from: gsJack on March 07, 2010, 02:24:52 PM
Here they are for all years, gotta put it on the Wiki one of these days.  The pic there is for the original 89-00 models only.

http://img.photobucket.com/albums/v443/jcp8832/GS500fuelcocks.jpg

when i redid my carbs that was the diagram i used to reconnect my hoses' the gas smudged my markings on the tubes....

Yep, the on and res hoses were crossed. Hopefully that fixes the problem, guess ill find out next time i run outta gas!

Update -- yah that was it. Seems kind of odd that my reserve runs out at about 120 miles while my regular line runs out at a normal (for me) 170. Any idea why this could be?

I would like to fix my reserve one day. ha

Quote from: JonM1211 on June 05, 2010, 11:40:24 PM
Update -- yah that was it. Seems kind of odd that my reserve runs out at about 120 miles while my regular line runs out at a normal (for me) 170. Any idea why this could be?

I would like to fix my reserve one day. ha

Easiest fix in the world.  

They are labeled wrong. 

Just swap the names and everything will appear to be working the way it should if you are averaging 40 mpg. 120 for normal, switch to res for additional 40-50.  

Quote from: JonM1211 on June 05, 2010, 11:40:24 PM
Update -- yah that was it. Seems kind of odd that my reserve runs out at about 120 miles while my regular line runs out at a normal (for me) 170. Any idea why this could be?

if you're going from less miles to more on your normal tank, it sounds like it was correct before. If the mileage increased it sounds like your running on your reserve tank now. 120 does sound extremely low for a normal tank and 170 sounds closer to normal, but I'm still confused how it was set up that you were getting the 120 in the first place??

Quote from: tt_four on June 06, 2010, 06:20:57 AM

Quote from: JonM1211 on June 05, 2010, 11:40:24 PM
Update -- yah that was it. Seems kind of odd that my reserve runs out at about 120 miles while my regular line runs out at a normal (for me) 170. Any idea why this could be?

if you're going from less miles to more on your normal tank, it sounds like it was correct before. If the mileage increased it sounds like your running on your reserve tank now. 120 does sound extremely low for a normal tank and 170 sounds closer to normal, but I'm still confused how it was set up that you were getting the 120 in the first place??

Swap the names normal and reserve and it makes sense. 

His original post said:

Quote from: JonM1211 on February 25, 2010, 12:51:21 AM..snip.. My bike uses about three gallons of gas and quits. The reserve doesnt work (never did) ..snip..

Older bikes have smaller tanks.
California, pre-2000: 4.0 total, 0.9 reserve     170/4 = 42.5 mpg
Non-CA, pre-2000: 4.3 total, 0.9 reserve       170/4.3 = 39.53488372093023 mpg
California, 2001+: 5.0 total, 1.0 reserve
Non-CA, 2001+: 5.3 total, 1.0 reserve

That makes sense, but I followed the diagram below to correct it.

http://wiki.gstwins.com/index.php?n=Main.HoseRouting


How many miles do you average before the reserve kicks in / total?

Quote from: JonM1211 on June 06, 2010, 03:54:47 PM
That makes sense, but I followed the diagram below to correct it.

http://wiki.gstwins.com/index.php?n=Main.HoseRouting


How many miles do you average before the reserve kicks in / total?

Mine is a 93 and my numbers are right in the same ballpark as yours is now.

I no longer have that metal tab that says res, pri, on, so I had to figure what was what by experimenting. 

I always try go by the philosophy, "If it ain't broke, don't fix it."