I recently removed my gas tank to do some work on the bike. On the underside of the gas tank are the connections/off-on valve for the fuel lines leading from the reserve switch thingymabob. My question pertains to that "on/off" switch on the underside of the tank. What position must it be in for reserve to work? Right now it's in the "on" position but my reserve isn't working. My tank just runs to empty with no prompt to switch to reserve. It appears my lines are connected properly. So could it be that simple little switch under the tank? Does that switch have to be turned "off" for the reserve to work???

Helpabrotha.

I think you have your fuel lines crossed at the tank.  Recheck them. I believe the tank petcock is on or off.

The valve that mounts under the gas tank needs to be in the ON position for ANY fuel to flow out of either fuel line.  If your tank is running completely empty, either your fuel lines are backwards, or your frame mounted petcock (reserve switch thingamabob) is set on PRI or RES.  Set it to ON, double check your fuel lines with the diagram on the GS500 Wiki, and see what happens.

I'll swap my fuel lines and see if that fixes the problem. Thanks.

The petcock under the tank only has two positions -- ON (screw slot should be up/down "|") and OFF (screw slot will be sidewars "--").

Quote from: 007brendan on June 25, 2010, 12:07:26 AM
The petcock under the tank only has two positions -- ON (screw slot should be up/down "|") and OFF (screw slot will be sidewars "--").

My 2009 has THREE positions for the petcock...........Off, on, and prime.........

THe actual petcock is vacuum activated, so it won't leak if left on.......it will actually only turn on when the engine is either cranking for start or running (when vacuum is applied).   If engine is not running then you can go to prime to let fuel manually flow to the carb (like if you just reinstalled carbs and the bowls are empty and need to be filled.

Cookie

Quote from: twocool on June 25, 2010, 03:16:05 AM

Quote from: 007brendan on June 25, 2010, 12:07:26 AM
The petcock under the tank only has two positions -- ON (screw slot should be up/down "|") and OFF (screw slot will be sidewars "--").

My 2009 has THREE positions for the petcock...........Off, on, and prime.........

007Brendan was referring to the valve attached to the fuel tank itself, which is either on or off, rather than the main/reserve selector.

BP should hire a few GSTwinners.  You guys have the petcock thing locked up!