I bought a 2001 Suzuki GS500 and it ran fine. It only needed a rear tire to pass safety and aside from the battery occasionally not being able to start the bike (I've bought a new battery and it starts fine now) there were no issues. Last Thursday I was leaving a friend's at 2:30am and as I was driving the bike died, I thought maybe switching to the reserve was necessary it wasn't. Now the bike starts, idles fine with the choke on, a little rough sounding though. Once the choke is off, it is idling too low (900rpms) then dies. And if I even start to open the throttle up it dies instantly. I have cleaned the carb jets, I have changed the battery, checked the choke and throttle cables and changed the spark plugs, now I am at a dead end and need some help.

First- will it run after its all warmed up?

Second - put the gas on prime- does this resolve the issue?

Third: after you cleaned the carbs- were one of the o-rings missing?

Fourth: adjust your idle screw on the bottom of the carbs higher.


People can help on how to diagnose #3 without tearing your carbs apart again. 

Did you fill up the tank?
Really - lots of new owner think they have gas when the tank is really almost empty.
True story: Friend came over to fix rough running of his bike. He said he had gas. Then he tore open the petcock and sis all sorts of other things. When I helped put the tank back on the bike I could tell the tank was empty. "Go down the block and fill it up THEN see if you still have a problem."

Problem solved: 4 gallons went into the tank.

Quote from: adidasguy on September 28, 2012, 11:23:06 AM
Did you fill up the tank?
Really - lots of new owner think they have gas when the tank is really almost empty.
True story: Friend came over to fix rough running of his bike. He said he had gas. Then he tore open the petcock and sis all sorts of other things. When I helped put the tank back on the bike I could tell the tank was empty. "Go down the block and fill it up THEN see if you still have a problem."

Problem solved: 4 gallons went into the tank.

+1

So there is gas, I had just put some in before it died on me, I also put more in when I thought I was out.
Second, all the seals and gaskets went back when I took them out. I have adjusted the idle screw a couple times, however it does look a bit worn out. Even when warmed up if I touch the throttle it dies, and I put it on prime to start the bike after cleaning the carbs, since then its started fine in the normal position

So on prime it works fine?

Check the float height with clear U-tube from the carb drain method.  Make sure you are getting the right about of gas into the bowl.  The gas level in the tube should be level with the float bowl gasket.  If it's not, your needle valves need adjusted or replaced.  Maybe they got damaged while cleaning the carbs.

no it doesn't work on prime.
I'll check the float levels. everything seemed to be in good condition when the carb was taken apart though.