Engine cutout when idle

[Insan3]

Hi all, long time since I have looked at the board!

I'm a bit of a bike novice and don't tend to get on my GS500 anywhere near as much as I would like due to the wet weather here in North Queensland. I think my problem may be due to lack of running

I've had a chance to do some ridingover the past few days and find that my bike cuts out on idle. Will not start unless choke is on full and despite being warm, it cuts out the moment I try to idle. Rode for about an hour, pulled up at some lights - stopped. Have no troubles re-starting as long as there are some revs given to it. Runs fine too from what I can tell, just gets 'jumpy' under 3000rpm.

Where do I start looking? Is it possible that is just a fuel issue? Stuff in the tank is probably about 3 months old now.....

Thanks guys

[Allen]

So does it stall everytime you come to a stop? Maybe some fresh oil and gas?

[Big Rich]

+1

If fresh gas doesn't do it, then it's time to clean the carbs. Specifically the idle jets.

[Insan3]

So does it stall everytime you come to a stop? Maybe some fresh oil and gas?

Yep, every time I come to a stop.

How do I go about draining the fuel tank?  I was considering going on a long ride to use 1/2 tank, then topup and repeat. Again - I'm a newbie when it comes to my bike 

[tb0lt]

I used to have this issue. I'm guessing your engine will die if you pull the right side (rear brake pedal side) spark plug wire. Try running with the left side spark plug wire disconnected. If it runs the same at low revs, then you've got a plugged pilot on the left carb.

[Big Rich]

So does it stall everytime you come to a stop? Maybe some fresh oil and gas?

Yep, every time I come to a stop.

How do I go about draining the fuel tank?  I was considering going on a long ride to use 1/2 tank, then topup and repeat. Again - I'm a newbie when it comes to my bike 

Nah, make sure the petcock is set to run or reserve. Then disconnect the fuel line from the petcock. Hook up another line from the tank and into an empty gas can. Then set the petcock to prime. And wait .......

[tb0lt]

So does it stall everytime you come to a stop? Maybe some fresh oil and gas?

Yep, every time I come to a stop.

How do I go about draining the fuel tank?  I was considering going on a long ride to use 1/2 tank, then topup and repeat. Again - I'm a newbie when it comes to my bike 

Are you assuming that the tank NEEDS to be emptied to remove it from the bike? Unless you actually NEED to empty out the tank , just undo it from the bike, securely hold the left side, lift up the right rear and use a flat head screwdriver to turn the little metal valve attached to the underside of the tank to shut off fuel supply. Once you do that, you can pull both rubber lines off the tank and the fuel will stay inside without needing to be drained.

[Allen]

Did it stall like this before? Or did all of a sudden you start having this stalling problem? Did it start to die once in a while, and overtime became more and more frequent til the situation you have now?  What is the bikes age, and mileage?  First of all, I would dump out the old gas into a clean container, if its clean mix it into your truck or car.  Check the oil level and viscosity. If the oil is low, or dirty, or too thin, I would replace it and the filter too.
To empty the gas tank, there are two hoses that lead from your tank to the fuel petcock, disconnect the battery, and one of the hoses going into the petcock and drain it into a clean bucket, I would reuse the gas in your car or truck if you think its still good. Get as much out of there as possible, put it in your car, then go get some fresh gas.  That probably won't fix the stopping = stalling issue.
My guess, is: 1) if your bike is pretty new, the carbs probably are clean (you can spray a little carb cleaner into the carbs when its running) (don't take it apart until you are sure it is the problem)
2) Your bike is new, but you never had the valve clearances checked or adjusted.

I ran my bike til it stopped working, (my right hand was the idle control), ended up that both exhaust valves need to be reshimmed.  There is an excellent video made by kerry walking you through every step for a valve adjustment.  I highly recomend you watch this video, and attempt to measure your valve clearances BEFORE you take your carbs apart.  My bike went from sitting, not running, to runs good as new after a valve adjustment, and have had no problems for over a year now.
Good Luck.

[Allen]

Yeah, you dont have to drain all the gas to remove the tank; I would also try what Tbolt suggested, running the bike sans right or left sparkplug, and see if you can notice a difference in performance between the cylinders, if they seem the same, I think your carbs are fine.

[Paulcet]

Running on one cylinder can be caused by clogged idle jet.