So fellas,

I have an 89 GS500E, bought it for riding while I'm trying to fix my other bike!  Anyways, My GS starts right up when warm, have to play with prime when cold, but it will still start and stay running after a few tries without enough gas while I warm it up. Sometimes she likes to bog down when I leave it unattended and don't add any throttle to help her stay alive. When the bike is warm and running good it seems to idle around 2 to 3 grand (tach cable is broken) and then when I try and adjust the idle screw to a lower idle 1/8 of a turn or so, it will bog down to like 500 or 1000 and seem like it wants to die. No idea why the idle screw is messed up, but I think all it needs is maybe a good carb cleaning and tank cleaning, because there is some rust in the tank that I know of. Any suggestions are appreciated! 

By the way, just last weekend I took it out for a 27 mile ride, seemed to do fine minus the fact that it was idling at 3 grand or so. Was going to go to Adidasguy's to get some dog bones but don't know if I trust the bike for a ride to Seattle yet haha.

I'm less than 27 miles away. I have tach cables.
Maybe just a good carb sync will help out.
I hate the weather right now. Noon and WS is still all fogged in. Up to 34* at my house. Probably lots of black ice on the roads.
When weather is good, come over.

If your bike is idling like that with the choke lever in the fully off position, check your cable routing. It's not uncommon for it to get wrapped around something it shouldn't and cause high/unstable idling like you describe.

If you can't get the choke lever to the off position without it stalling, it's most likely your idle mix screw(s) are out of adjustment or gummed up.

If neither of those are the case, check your spark plugs to see if you can get any hints.

Haha I know the weather is getting on my nerves, forecast just changed from nice and sunny tomorrow to freaking foggy and like 40 degrees again. I really wanna come over, I'll put your address into maps and see how far it is from mine. Never done a carb sync before, might need your assistance. Bike should get over there no problem. And Badot the choke cable works fine, goes on and off with a clear change in rpms. But I think that the idle screw might be gummed up, only way to know is to check.

Oh, and don't forget to look for vacuum leaks as well -- do your revs hang if you rev it from idle?

Yea, I'm sure it has some vacuum leaks as well. Just went out and started it up with a little difficulty thanks to the thirty degree weather. But revving it at idle seems to not hang as much as when i bought it, which I'm glad. However; after revving out would go from normal idle to a semi high idle and hang there for a bit. she sat for a while before i bought her so continuous riding this summer should do her some good.

My bike has just started doing some weird stuff like this as well.

Last weekend I took it for a 380km round trip. Ran perfectly.

Tonight I noticed it died pretty quickly after starting with no choke. Gave it some choke and it really struggled to start. It was very stall prone at low revs. Had to give it quite a bit to get moving. This is very unlike my bike as it usually pulls fine from very low revs.

Thought it might just need to warm up so went about riding. When revs are up and at riding speeds, The bike is fine. its just when you get to the lights, it wants to die all the time.

Something else that is weird is that when you give it choke, it dies. So it seems to me like something is up with the fuel mixture but I really have no idea where to start.

About 800km ago it had a full 24000km service and had been running great since then.

It's late so I'll check the plugs for any hints tomorrow but in the mean time, if anyone thinks this sounds familair or has any ideas, I'd love to hear them.

Cheers!

Quote from: andrewf on January 22, 2013, 05:16:25 AM
My bike has just started doing some weird stuff like this as well.

Last weekend I took it for a 380km round trip. Ran perfectly.

Tonight I noticed it died pretty quickly after starting with no choke. Gave it some choke and it really struggled to start. It was very stall prone at low revs. Had to give it quite a bit to get moving. This is very unlike my bike as it usually pulls fine from very low revs.

Thought it might just need to warm up so went about riding. When revs are up and at riding speeds, The bike is fine. its just when you get to the lights, it wants to die all the time.

Something else that is weird is that when you give it choke, it dies. So it seems to me like something is up with the fuel mixture but I really have no idea where to start.

About 800km ago it had a full 24000km service and had been running great since then.

It's late so I'll check the plugs for any hints tomorrow but in the mean time, if anyone thinks this sounds familair or has any ideas, I'd love to hear them.

Cheers!

Sounds like you may have a vacuum leak.  But check the plugs to give you direction on lean or rich.
Also, check float height via the U-tube drain method on both carbs to let you know that both carbs are getting the correct amount of fuel.

What things were done at the 'full' service?
Just trying to get an idea of any past maintenance such as last valve check, carb sync, etc..

- Bboy

Quote from: jacob92icu on January 19, 2013, 12:34:43 PM
So fellas,

I have an 89 GS500E, bought it for riding while I'm trying to fix my other bike!  Anyways, My GS starts right up when warm, have to play with prime when cold, but it will still start and stay running after a few tries without enough gas while I warm it up. Sometimes she likes to bog down when I leave it unattended and don't add any throttle to help her stay alive. When the bike is warm and running good it seems to idle around 2 to 3 grand (tach cable is broken) and then when I try and adjust the idle screw to a lower idle 1/8 of a turn or so, it will bog down to like 500 or 1000 and seem like it wants to die. No idea why the idle screw is messed up, but I think all it needs is maybe a good carb cleaning and tank cleaning, because there is some rust in the tank that I know of. Any suggestions are appreciated! 

It's tough to know what to do with this, without knowing what rpms its at for sure... not doubting your ability to estimate here, as clearly you can tell something is wrong... but its just hard to add things up without concrete symptoms... and rpms at different levels can tell you different things. Rough idle and hanging throttle response is tell tale of a vaccum leak, though, if that is what you are experiencing... and it can act differently from cold to warm conditions.  Most common place for a leak is at the carb boots.  Spray carb cleaner around that to see if rpms change to confirm a vacuum leak there.

- Bboy

I'll be sure to do that. But i took it out for a ride and it actually ran pretty well same pretty low idle the whole time. It sat for a while so i think that just having some gas run through it constantly is making it run a little better.

Quote from: BockinBboy on January 22, 2013, 07:41:19 AM

Sounds like you may have a vacuum leak.  But check the plugs to give you direction on lean or rich.
Also, check float height via the U-tube drain method on both carbs to let you know that both carbs are getting the correct amount of fuel.

What things were done at the 'full' service?
Just trying to get an idea of any past maintenance such as last valve check, carb sync, etc..

- Bboy

Valve clearance was adjusted and carbs were synched.

Just went and had a poke around and it looks like one of the plugs is very dark, but dry. The other looked a nice light tan colour. Both plugs are sparking and I even tried putting another (old and used but clean) plug in and it went black pretty quick.

Have called the place where the service was done and they sounded a bit perplexed as everything that could be responsible was checked and either given the OK or replaced during the service. Am taking it in next week for the mechanic to look at and will report my findings here.

I'm not that well equipped to do much tearing down of my bike as I live in an apartment block with so many rules about what we can do in the car park.

Thanks for your help!

hahaha wow that sucks about not being able to work on your bike or anything where you live . And thats strange, that would be a first for me about one spark plug turning a dark color. Definitely keep us posted.

Hey bboy, you can also use wd40 to spray around the carb boots and listen for a change in rpms right?

Quote from: jacob92icu on January 22, 2013, 06:17:15 PM
Hey bboy, you can also use wd40 to spray around the carb boots and listen for a change in rpms right?

Yeah, you can but... the rpm change isn't as easily detected/noticed with WD40 as it is with carb cleaner.  I'd give it a shot since its a little more likely a person would have WD40 near the toolbox versus carb cleaner.  But if the WD40 doesn't detect it, don't mark it off the list just yet.

- Bboy

Yea thats what I was thinking. I mean I could go get carb cleaner but I have heard about doing it with WD too. Thanks for the suggestion!

Hi Guys

Update on my bike.

The morning I took it down to the shop to get looked at, it ran fine after a 15min blast down the freeway. Idle was back to normal and low rev power was back. Typical!

Explained the situation to the guys at the shop and they said they'd have a look at it anyway if I liked. Figured it was better to get a professional opinion.

They couldn't fault the bike while they had it there (of course) but said there was some build up in one of the carb float bowls. They gave it a clean and tested it some more. Been on a couple of big-ish rides since then and it's fine again.

They also suspected a stuck float based on the symptoms I described earlier and the crud in the float bowl.

So, if anyone else ever has this kind of issue, check that!

Cheers
Andrew

So the shop just cleaned your carbs and now your bike is fine? Congrats!

I had the same thing happen a few weeks ago, only twice in a single day. It was about 60 degrees out. I started it at home, it died, gave it full choke and it would still die. After a minute with some throttle to 2-3000, it stayed running fine. Thought it was weird but continued on because it was in the shade and the sun hadn't hit it yet that day. But that's the first time it's died WITH full choke even in very cold weather.

So then I rode to the store a few miles away on the freeway, went in for abut 15-20 minutes, came out, and it wouldn't start, even with full choke. Ran it for a few minutes at 3000 and full choke, it still died. Did that a few times and it still kept dying. I increased the idle a tad and it started up like normal without dying, even took the choke off pretty quickly. I also noticed it had a sticky choke and someone else I talked to said he had the same problem on his 99 gs500 a few years ago and he fixed the sticky choke and didn't have any more problems (not sure why, doesn't sound quite right, but hey that's what he said).

Haven't had the problem since, even in cold weather. I also let it sit for the last week and started it up today with no problems and no choke needed.

So before it was idling about 1200, now it's set to about 1400 I think. Right now when I start it, it goes to 1000, within 10 seconds it's at 1200-1300, then slowly climbs to 1300-1400 where it remains. I'm going to check out the sticky choke first, but I'm about to give it a full service check since I bought it used a few months ago and I just bought the repair manual to do a full walk-through I've been wanting to do anyway. I will post again once I've done a full checkup or find anything beforehand. And maybe try out what's already been suggested.

Maybe my thorough explanation might help someone.

Quote from: jacob92icu on February 03, 2013, 07:03:42 PM
So the shop just cleaned your carbs and now your bike is fine? Congrats!

Well technically it was actually running fine before they even looked at it. So I guess whatever was stuck, came unstuck. Anyway, the clean set my mind at ease so it's all good!