GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: Bluesmudge on February 03, 2010, 12:53:07 PM

Title: Is it my CARBURETORS or ...??????
Post by: Bluesmudge on February 03, 2010, 12:53:07 PM
Okay, so I'm riding home from my grandfather's last night. Almost home and gunning it to keep up with this a$$ of a harley rider when all of a sudden my bike acts like its out of gas so I try putting it on RES but it doesn't do anything and eventually dies. I coast into a parking lot.

Symptoms:
-I have a non-locking gas cap, so gas theft is an option (its happened before).
-I had 1 gallon of gas delivered to me thinking my problems would be solved but the problems continued.
-Bike would idle fine but die if load was put on the engine or throttle turned more than 1/4
-As the bike warmed up more and less choke was needed the bike ran worse and worse at idle.
-Once fully warmed up from sitting at idle I could no longer get the bike to start.
-After sitting for ~15 minutes the bike could idle again
-Starting issues were not battery related as I had a car to jump me when my battery died from messing with the bike for so long.

After 3 hours I had the bike towed back to my house.
Since the issue is obviously not lack of gas in the tank and yet it is acting as such, I can only guess that it is a carb problem. I don't have a fuel filter so maybe some crud got sucked into the mid/main jets when I was keeping up with that Harley guy on the strait away.
2006 GS500F with 19700 miles

What do you guys think? Is there anything else I can do other than attempting to clean the carbs?

Title: Re: Is it my CARBURETORS or ...??????
Post by: black and silver twin on February 03, 2010, 12:59:52 PM
could also be petcock not flowing gas, they are vacuum operated and the diaphragm can break although that is unlikely on such a new bike. try putting the petcock on PRI. if it fixes it then your petcock or vacuum line is bad.
Title: Re: Is it my CARBURETORS or ...??????
Post by: Bluesmudge on February 03, 2010, 01:06:13 PM
I did try running it on PRI and it didn't help at all, which rules out the petcock, correct? If not, I happen to have a spare.
Title: Re: Is it my CARBURETORS or ...??????
Post by: bassmechanicsz on February 03, 2010, 01:08:02 PM
It almost sounds like your tank vent might be clogged.  Have you tried running the bike with the gas cap open to allow for venting.  Just another simple thing to try.
Title: Re: Is it my CARBURETORS or ...??????
Post by: trumpetguy on February 03, 2010, 01:08:37 PM
Could be flooding caused by needle valve seat o-rings.  That's kind of how mine was acting.  When running, the petcock was allowing fuel to flow, but the fuel in one carb was not being metered by the float valve (it was bypassing it through the faulty o-ring).

Difference was, mine wouldn't idle, but would run WFO throttle.
Title: Re: Is it my CARBURETORS or ...??????
Post by: Bluesmudge on February 03, 2010, 04:33:37 PM
Thanks for the help, I'll look into each of those soon. Will second my thoughts of clogged jets as a possibility?
Title: Re: Is it my CARBURETORS or ...??????
Post by: centuryghost on February 03, 2010, 04:44:26 PM
I would check/clean your carbs. It totally sounds like jets to me. Mine was kinda the opposite; I would stall and die under load or over half throttle. Ended up being a clogged main jet. Yours might be a pilot clog. I would drain the bowls and pull one off to see if there's rust collecting at the bottom.
Title: Re: Is it my CARBURETORS or ...??????
Post by: Bluesmudge on February 08, 2010, 01:43:06 AM
Thanks for help!

Over the weekend I took the jets out and cleaned them with some carb cleaner. I'm not sure that was the issue, they seemed extremely clean.
I also emptied my gas tank. The gas seemed diluted or something, I'm thinking rain water somehow got into the tank in a large quantity. Not sure though.

So the verdict is: Clogged carbs or water in the gas. Whatever it was, I fixed it! Runs great now.