only runs on prime...

[vhmpyr]

Well, thats the problem I am having... When I start the bike the engines stall right away... I put on full choke and it does the same thing...it stalls too  ....but then if I put the bike on " prime " it runs fine but as soon as I put it back  to "on" it slowly stalls to death  ..........can somebody tell me whats wrong with the bike and things that I might have to look for... I need help ...the bike is a 2006 and believe it or not ( and im going to get crussified for this ) it only has 350 miles on it.

[CndnMax]

This may sound like a stupid question but is there enough gas in the tank? did you try to run it on reserve?

[vhmpyr]

yup...half tank full... or is it half empty

[Kerry]

If you can see the "hump" in the bottom of the tank, the first thing I'd do is fill 'er up and repeat the test.



I can't vouch for the exact state of my bike when I took the pic in Oct 2004 (whether I was on REServe or not).  But if this snow EVER melts and I get to run it down to REServe again, I'll take another pic and do a better job of naming the file.

[lamoun]

If in the PRIME position there is gas then is should not be a fuel level matter.

Look for the carburetor vacuum hose, it might be pinched.

[Kerry]

If in the PRIME position there is gas then is should not be a fuel level matter.

I respectfully disagree.  I'm not saying that it IS a fuel level matter, but that it still could be.

When the fuel selector switch is in the ON position, it allows fuel to pass from the rear hose (as attached at the tank-mounted petcock).  When it is in the RES or PRI position, it passes fuel from the forward hose.  The "drain" for the ON hose is higher inside the tank than the "drain" for the RES/PRI hose.

So ... if there is one gallon (or less) remaining in the tank, and the fuel selector switch is in the ON position, no fuel will pass to the carburetors and the engine will eventually "starve".  But if the switch is moved to RES or PRI fuel will still pass from the other hose.  (If the bike won't run in the RES position, refill the carburetor float bowls by switching to PRI for 30 seconds or so.)

Could the symptoms match a different condition (like a pinched or disconnected vacuum hose)?  Certainly.  But I would start by adding at least a gallon (or two) of fuel to the tank and retesting before looking deeper.

[kml.krk]

once I thought it was half empty too!. I realized it wasn't when she died on the left lane on the highway doing 80 MPH.
At first I didn't know what happened, but I tried reserve and she fired right away, at the next exit I found gas station - over 4 gallons I poured inside the tank.
The fuel level indicator would be nice, wouldn't it? 

cheers
KaMeL

[ben2go]

Here's a couple links to fix a bad petcock.



http://gstwins.com/gsboard/index.php?topic=19363.0



http://gstwins.com/gsboard/index.php?topic=36958.0

[galahs]

The 2004-2007 models have a different petcock. So better to see this thread...
http://gstwins.com/gsboard/index.php?topic=37366.0

[CndnMax]

before digging into the petcock first fill it up and try, if that doesnt work look for a pinched line under the tank and the vacuume line. It only takes a few min and then you can dig into the petcock.

[vhmpyr]

weekend is coming....as soon as get a chance I will try and fill her up...I hope thats all the problem I got.

[galahs]

You can test if its the vacuum by seeing if it runs on reserve. Reserve is also vacuum operated but as Kerry mentioned, uses the lower fuel exit (as used by Prime)

[lamoun]

When the fuel selector switch is in the ON position, it allows fuel to pass from the rear hose (as attached at the tank-mounted petcock).  When it is in the RES or PRI position, it passes fuel from the forward hose.  The "drain" for the ON hose is higher inside the tank than the "drain" for the RES/PRI hose.

So ... if there is one gallon (or less) remaining in the tank, and the fuel selector switch is in the ON position, no fuel will pass to the carburetors and the engine will eventually "starve".  But if the switch is moved to RES or PRI fuel will still pass from the other hose.  (If the bike won't run in the RES position, refill the carburetor float bowls by switching to PRI for 30 seconds or so.)

You are right, I should have said "If in the PRIME position there is gas, and the problem persists with the fuel selector in the RES position, then is should not be a fuel level matter"

[Kerry]

I should have said "If in the PRIME position there is gas, and the problem persists with the fuel selector in the RES position, then is should not be a fuel level matter"

I (respectfully) agree with that! 

[vhmpyr]

I did not wait till the weekend and put some gas today......I feel stupid cause now the engine runs at " on " position...hey to my defense I thought I had plenty of  gas.....although sometimes when I engage the throttle it sounds and feels like its going to stall, like it has a dirty carb or something....but hey at least now its running.

[Kerry]

Don't feel bad ... the same thing happened to me the first day I got my bike.  "It sure looked like there was plenty of gas in there!" 

Thank goodness there was enough to ride it home on PRIme.  (Whew!)  It was a long time before I understood WHY the bike had acted that way....

[CndnMax]

I did not wait till the weekend and put some gas today......I feel stupid cause now the engine runs at " on " position...hey to my defense I thought I had plenty of  gas.....although sometimes when I engage the throttle it sounds and feels like its going to stall, like it has a dirty carb or something....but hey at least now its running.

don't worry your not the first, nor the last, to fall victim to the full yet empty gastank illusion 

[scottpA_GS]

....although sometimes when I engage the throttle it sounds and feels like its going to stall, like it has a dirty carb or something....but hey at least now its running.

As little as you seem to ride it, I would guess there is some buildup in the carbs, You can ad a bit of carb/injector cleaner to help instead of tearing apart 2 y/o carbs

[ben2go]

The 2004-2007 models have a different petcock. So better to see this thread...
http://gstwins.com/gsboard/index.php?topic=37366.0

One day I'll learn not to post when I'm tired and half asleep.