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Main Area => General GS500 Discussion => Topic started by: kingfish007 on October 17, 2010, 07:16:18 PM

Title: Sudden Carb(?) Problem on '05 GS500F
Post by: kingfish007 on October 17, 2010, 07:16:18 PM
OK, to start with my bike has about 10,000 miles, and I've never had a problem with anything on it.  All I've had to do has been change tires, oil, and a clutch (thanks to the PO's kid).

I noticed my inspection sticker had expired at the end of August, so it sat for about 4-5 weeks, because I was lazy.  I ran it around the block a couple of weeks ago just keep the battery charged, and everything was OK.

Now when I cranked it 3 days ago, it won't run right.  It will only run with the choke on, and the idle just surges up and down drastically.  If you give it any amount of throttle, it either bogs or dies. I can normally turn off the choke after a couple of minutes, but now it must stay on about 1/2 even when the engine is warm, just to to keep it running.

Fuel/vacuum line look OK (don't see any damage or cracks). Gas cap open or closed, and petcock position made no difference either.

Bad gas, carbs plugged, petcock, or any other ideas where to start?

Thanks,
Smitty
Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: Big Rich on October 17, 2010, 07:38:19 PM
The gas shouldnt be old enough to cause your problem, but it certainly isnt helping at all. I would drain it and try some fresh stuff.

How long did it run with the choke on? If the fresh gas doesnt help your problem, try cleaning the idle jets first, then maybe the entire carbs.
Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: mister on October 18, 2010, 12:59:23 AM
Check your plugs and leads - one, to make sure spark is constant and two, to see if your plugs are... not right.

Michael
Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: the mole on October 18, 2010, 01:59:57 AM
Could be that jets are clogged from it sitting and the fuel evaporating out of the float bowls, leaving some cr@p behind. If you're lucky a long run might clear it, otherwise its carb cleaning time.
Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: kingfish007 on October 18, 2010, 07:11:58 AM
Last night I got it to rev up some, after it was warmed up.  It would bog, pop, and rev really slow. Had to feather the throttle to keep it from stalling, and when I let off the throttle it would die. 
Never could turn the choke off or it would just die, Normally with the choke on, it holds a steady rpm, but now it will go up/down about 2000rpms at whatever position you set it.

I guess I'll start with some new gas first.  Seems strange it would do this all of a sudden - well in a period of about 1-1/2 months setting idle.

Thanks,
Smitty
Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: bigfatcat on October 18, 2010, 08:51:54 AM
Quote from: kingfish007 on October 17, 2010, 07:16:18 PM
OK, to start with my bike has about 10,000 miles, and I've never had a problem with anything on it.  All I've had to do has been change tires, oil, and a clutch (thanks to the PO's kid).

I noticed my inspection sticker had expired at the end of August, so it sat for about 4-5 weeks, because I was lazy.  I ran it around the block a couple of weeks ago just keep the battery charged, and everything was OK.

Now when I cranked it 3 days ago, it won't run right.  It will only run with the choke on, and the idle just surges up and down drastically.  If you give it any amount of throttle, it either bogs or dies. I can normally turn off the choke after a couple of minutes, but now it must stay on about 1/2 even when the engine is warm, just to to keep it running.

Fuel/vacuum line look OK (don't see any damage or cracks). Gas cap open or closed, and petcock position made no difference either.

Bad gas, carbs plugged, petcock, or any other ideas where to start?

Thanks,
Smitty

Sounds like your battery may be in a very low state of charge - believe it or not a discharged battery can cause a vehicle to run poorly and make you think you've got all kinds of problems due to carbs, fuel, etc.

Title: Re: Sudden Carb(?) Problem on '05 GS500F
Post by: The Buddha on October 18, 2010, 09:50:26 AM
Has it gotten colder significantly in the 5 weeks since your last good run ?

How much colder ?

2 possibilities - you have water in the gas. Yes get new gas but water will need to be integrated back into the fluid - water separates and gets to the carbs where it ruins the fun. Alcohol will restore the fun as alcohol always does, we give it to stuck up girls and suddenly they are much more fun ... only this alcy hooool ... hash to bee ishopropyl achyhooowwwl ... sho yous jushht git shum Heeeeet fer et.

Then the second - you may need a valve adjustment. It can happen with tight valves, and colder = tighter for that.

Cool.
Buddha.