I bought the bike a few days ago from a guy I work with. He bought it new in 2006. Had put 4200 miles by 2010, he then bought a new K1600GT BMW a few years ago and that meant the GS sat in the garage ever since. The bike is in great shape, but again, it hasn't been run since sometime in 2010. Fast forward to last week. His wife was getting irritated with the non-running, taking up space, motorcycle sitting in the garage taking up space. I buy the bike for $830 and get it to my house. I have since washed it up, determined that it wasn't getting gas. I then put a carb kit in each carb. It now runs like a top, but when warm it idles very high (3600-4000rpm's). After the fact, when I mentioned the high idle the previous owner mentioned that it had been doing that for awhile. He also stated that it had never been in for any kind of carb service, so they are were/are as delivered from Suzuki.
So I did try to search on this site for threads concerning the high idle. Here are the things I have tried to do per the posts in those threads that I figured were similar to mine.
1) I sprayed starter fluid all around everything coming to and from the carb. In particular the connector between carb and manifold, all of the vacuum hoses. I saw no difference in idle.
2) Checked the throttle blades on each of the carbs and they both seemed to be exact with the other one. I realize that there are better ways of syncing them, but surely I wouldn't get a crazy high idle like that would I as long as they are close?
3) The throttle cable is adjusted properly and there is slack when at idle in the cables. And of course the idle adjuster knob on the bottom of the carb assembly is backed off to where it's not touching anything.
It seems to be worse after warming up some, then when completely cold. I have checked the action of the choke very closely and it opens and closed freely. It seems rather odd to me though that the bike doesn't want any choke at any time, even when dead cold? Any relation between the high idle and no choke being needed?
I haven't messed with the TPS, but I wondered if it was set incorrectly if that could cause the issue? And what voltage should it be at idle?
Just a quick pic or two of how it looks...
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/leftsidegs500f_zpsedfa57b3.jpg)
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/leftgs500f_zps86959498.jpg)
I suggest you set idle when FULLY warmed up. Others here have had success with hanging idle that way. However, you do say that the idle adj screw is backed all the way off.... always? or just when you were checking it's operation?
How is the air filter? Is it OEM, or K&N drop in? If K&N drop in, it needs the restrictor ring.
It might be as simple as syncing the carbs.
If you don't have the tool, here's the Hillbilly Carb Sync method:
Bike running. Warmed up. Tank off so you can get to the carb balance screw. You may have to adjust idle while doing this.
Pull one plug wire and note how much engine slows down. It may stall or nothing may happen at all.
Plug in and do same to other side.
Notice any difference? If so, turn carb balance screw.
Repeat.
Worse? Turn other way.
Better? Turn more until they are balanced.
Balanced means unplugging either wire will make the engine slow down the same amount.
Now adjust idle for proper speed 11k-13k rpm.
The idea is to get each cylinder doing the same amount of work. if you pull a wire and the engine really slows down or stalls, then that side is doing most of the work. If you pull a wire and not much happens, it means that side isn't doing much at all compared to the other side. You adjust the screw until both sides are doing the same amount of work. In principle, that's what the carb sync tool does my measuring the vacuum in both carbs.
You got one hell of a deal! I would have jumped on that in a heartbeat!
For comparison, I just bought a 2001 E version (naked) with 5k miles, good condition for 1600 -_-
Quote from: adidasguy on March 12, 2013, 10:41:12 PM
It might be as simple as syncing the carbs.
If you don't have the tool, here's the Hillbilly Carb Sync method:
Bike running. Warmed up. Tank off so you can get to the carb balance screw. You may have to adjust idle while doing this.
Pull one plug wire and note how much engine slows down. It may stall or nothing may happen at all.
Plug in and do same to other side.
Notice any difference? If so, turn carb balance screw.
Repeat.
Worse? Turn other way.
Better? Turn more until they are balanced.
Balanced means unplugging either wire will make the engine slow down the same amount.
Now adjust idle for proper speed 11k-13k rpm.
The idea is to get each cylinder doing the same amount of work. if you pull a wire and the engine really slows down or stalls, then that side is doing most of the work. If you pull a wire and not much happens, it means that side isn't doing much at all compared to the other side. You adjust the screw until both sides are doing the same amount of work. In principle, that's what the carb sync tool does my measuring the vacuum in both carbs.
What he said ^^^^^. now, you said you put carb kits in it?, lemme ask, when you did this, & had it stripped down, did you dunk the carbs in cleaner for say 24 hours? ( works wonders)
1st off thanks for all the excellent, quick replies!! The idle screw is backed all the way out, its not touching anything at all. It still has the stock filter, which looks like new. And by the way, the whole bike is completely stock. I have not tried the sync method described, ill give it a shot. You don't suppose harbor freight sells a cheap sync tool? I didn't dunk carb in cleaner at all. I did however shoot carb cleaner in every passage I could see and bought a high-e guitar string and feed that down every passage I could find and each jet (years).
The TPS voltage can't do this? It's bothering me that previous owner said it has been doing this for awhile.
My vote is the air screws. Take out the brass plug and set to 2.5 turns out. Use the search feature on the procedure.
I think it's running lean. Mine did it STRAIGHT out of the showroom. I was so pissed that I took it back and they said no problem, and 30 minutes later was back to normal.
Later on I found out that they messed with the air screws. Thank the EPA for the lean mixture.
Quote from: goat-ee on March 13, 2013, 04:53:39 AM
1st off thanks for all the excellent, quick replies!! The idle screw is backed all the way out, its not touching anything at all. It still has the stock filter, which looks like new. And by the way, the whole bike is completely stock. I have not tried the sync method described, ill give it a shot. You don't suppose harbor freight sells a cheap sync tool? I didn't dunk carb in cleaner at all. I did however shoot carb cleaner in every passage I could see and bought a high-e guitar string and feed that down every passage I could find and each jet (years).
The TPS voltage can't do this? It's bothering me that previous owner said it has been doing this for awhile.
I have to chime in here again. I have use the Harbor Freight Sync tool method. Here's what you need:
2' 3/16" aquarium tubing.
2 Harbor Freight 93547 Vacuum Gauge http://www.harborfreight.com/fuel-pump-and-vacuum-tester-93547.html
2 Aquarium Gang Valves
2 Universal size vacuum couplers.
Here's how to do this...
Cut off a small piece of 3/16 tubing and attach to the vacuum barb in the carb. Then take the other end and attach to the Aquarium Gang Valve (more on this in a minute). Then use the universal coupler to connect to the vacuum gauge. Do this for each side.
The aquarium Gang Valve is used to regulate vacuum pressure. You want to sync at idle, and without the gang valve, the gauge will flutter such that you cannot get a reading. Restricting the pressure will make sure that the needle only fluctuates a little.
I don't have a writeup or pics, but search for "Weedahoe Harbor Freight" for more info. He didn't use a gang valve, but I recommend that you do.
Check the simples, and confirm things before tearing into anything in depth. These take but a few minutes and will be worth their time... Heck, they are worth their time without having any noticeable issues!
1.) Pull the plugs, and read them... use it to confirm leanness, richness, or neither!.... heck that could send you back to checking the throttle cables if its neither...
2.) Check the float height using the clear tube U-bend method. Check the fuel delivery level and use that to help diagnose.
3.) Have you tried running the bike in Prime vs. On to see if there was a difference?
- Bboy
Quote from: adidasguy on March 12, 2013, 10:41:12 PM
It might be as simple as syncing the carbs.
If you don't have the tool, here's the Hillbilly Carb Sync method:
Bike running. Warmed up. Tank off so you can get to the carb balance screw. You may have to adjust idle while doing this.
Pull one plug wire and note how much engine slows down. It may stall or nothing may happen at all.
Plug in and do same to other side.
Notice any difference? If so, turn carb balance screw.
Repeat.
Worse? Turn other way.
Better? Turn more until they are balanced.
Balanced means unplugging either wire will make the engine slow down the same amount.
Now adjust idle for proper speed 11k-13k rpm.
The idea is to get each cylinder doing the same amount of work. if you pull a wire and the engine really slows down or stalls, then that side is doing most of the work. If you pull a wire and not much happens, it means that side isn't doing much at all compared to the other side. You adjust the screw until both sides are doing the same amount of work. In principle, that's what the carb sync tool does my measuring the vacuum in both carbs.
I did as described. Each cylinder I got the same result. Instead of 3500rpm idle, it would drop to 14-1500rpm and hold there. Same rpm on both cylinders. So I guess that removes syncing of the carbs as a variable. I hadn't mentioned it before, but I did change out the spark plugs before I ever got it running. Just to to remove a possible issue. I'm attaching a couple of pics of how they looked.
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/IMAG0170_zpscfa4b84e.jpg)
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/IMAG0172_zps8ff46726.jpg)
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/IMAG0171_zps2e9eec05.jpg)
As was suggested I have tried changing from prime to on and to reserve. Makes no difference.
I think I am going to do as jestercinti suggested and remove the brass covers and adjust the air screws to 2.5 turns out. If the bike had always (?) idled high maybe they were adjusted wrong from the get go, or backed out over time? Would backing out of the idle screws cause this issue or is it usually being screwed in too much? I need to get ahold of the previous owner and check if it always idled high, or if it was just toward the end of ownership. He did mention it idling high, but to be honest I didn't ask many questions about that at the time. I was more worried about it not running at all.
Question: Is choke on with the lever pushed up or down? I have been saying it doesn't need any choke, but it's hard to tell by the picture by the lever which is on and which is off?
Here was a video I took right after I got it running. I thought I had it the way I wanted it when I took the video, then when warm I realized it idled really high.
(http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/th_VIDEO0007_zpse63c2c14.jpg) (http://i44.photobucket.com/albums/f8/no1jophus/Suzuki%20GS500F/VIDEO0007_zpse63c2c14.mp4)
Choke ON is pulled towards you. Off you push lever forward away from you.
Quote from: goat-ee on March 13, 2013, 11:52:43 PM
Question: Is choke on with the lever pushed up or down? I have been saying it doesn't need any choke, but it's hard to tell by the picture by the lever which is on and which is off?
I remember thinking this same thing at the MSF course... first day I had it wrong, and my bike kept dying (we were only doing friction zone stuff anyway), but it was a little embarassing thing to learn in front of everyone :embarrassed:
- Bboy
I drilled the brass caps of he idle screws. One carb was right at 2.5 turns out, the other was 1.75. Adjusted them both to 2.5 turns and I have the exact same issue. I got to looking at the TPS and wondered if maybe it could stop the throttle blades from returning completely. Nothing binding up so ruled that out. So I then adjusted it and that didn't help either way.
Another thing I hadn't mentioned, but I do notice that the mid-range while driving is soggy, and even stumbles pretty good especially when cold. Once past that, it will rev cleanly to redline. What should this tell me?
I'm about out of options aren't I? Would the floats being high or low cause this? What are my other options?
You have 3 jets.
Pilot for low speed
Mid for middle
and the third for high speed.
Bad middle would point to the mid jet or the associated stuff. I forget but there probably is an air passage to it that could be dirty.
Floats too low could cause it
Went to unhook one of the vacuum hoses to remove carb and it tore. Upon closer inspection a couple of the others looked kind of dry rotted. I decided to go ahead and replace all of the vacuum hoses in case there may have been a leak in one of them. It did no good of course.
I am now thinking I should check on the operation of the vacuum solenoid. If for some reason it was failed open wouldn't that be about the same thing as a vacuum leak as far as the carbs are concerned?
I plugged all vacuum sources going to the engine...no difference. I did finally get the oil changed and then decided to take it on a nice long ride with the hope that maybe a passage inside the carb was plugged and maybe with the high 70 degree temps today and riding it for a good long while would maybe unplug something!! About an hours driving and 5-6 runs to redline made no difference. Although I didn't notice the mid-range bog I had noticed before.
Something I noticed on my drive that I thought I should mention. Coming to a stop if I would lug the engine down to say 2k rpm, the engine would start to stutter and if I didn't give a little gas it would eventually die. It would start right back up and immediately go back to the 3.5K rpm idle.
Why would it want to stutter and die if brought to a lower rpm?
It was mentioned above by Paulcet that my idle issues could be caused by low floats. Could that also account for the other issue of wanting to die if pulled to lower rpm's?
Valves in spec?
You cannot tune a carb without valves in spec...I'd check them.
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I finally got inpatient and bought new carbs on ebay. http://www.ebay.com/itm/09-Suzuki-GS500F-GS500-500-CARBURETOR-CARB-CARBS-/190811583313?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWNX%3AIT&nma=true&si=eFDiBw5PVG6UTKR%252FJuUzllHgoUU%253D&orig_cvip=true&rt=nc
I guess we'll see if it acts different or not?
Quote from: goat-ee on March 19, 2013, 07:51:06 PM
I finally got inpatient and bought new carbs on ebay. http://www.ebay.com/itm/09-Suzuki-GS500F-GS500-500-CARBURETOR-CARB-CARBS-/190811583313?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWNX%3AIT&nma=true&si=eFDiBw5PVG6UTKR%252FJuUzllHgoUU%253D&orig_cvip=true&rt=nc
I guess we'll see if it acts different or not?
The carbs came, I installed them...
Runs like a brand new bike. I now have to choke it when cold, then as it warms up I can slowly take away choke, just as you'd expect. It then settles to a perfect 1200rpm idle. Anyone want the old carbs for REALLY cheap? $10 plus actual shipping?
You got a smoking deal. I would have bought that bike without hesitation.
My bet is that the valves are out of spec. Were you careful to check for the little rubber o-rings in the carbs?