07 GS500f idle issue

[Rx_only]

Hello, this is my first bike and after purchasing it and having it stored for a few months I realized after starting ang warming up the bike that it idles high once warmed up and it takes a while to return to idle after revved up. The idle starts normal but after warning up for 15 mins once I rev it the idle goes down slowly and hangs at about 3k. The throttle snaps back fast with a little play but not much.
A perfect example here (not my bike) http://youtu.be/obbaeDCFhFE
My bike had 13,700 miles. Any input would be awesome!

[Dr.McNinja]

• Check clutch cable. Make sure there's no snag in it's operation and moving the bars full lock left and right doesn't activate it.
• Make sure your filter is clean.
• Make sure your carbs are getting enough fuel.
• Spray water on the carb boots looking for bubbles. This will tell you if you have a vacuum leak once the bike heats up.
• Check all vacuum and fuel lines.
• Test carb synchronization
• Finally, if synching carbs doesn't fix it, pull the carbs, clean them, resynch them.
• Check exhaust valve clearances, tight exhaust valves can present as a hanging idle. Make sure to resynch the carbs if you change any shims.

It is very likely dirty/unsynchronized carbs. If you want, skip to that step and I can almost guarantee it will fix it. But the other steps are done along the way to pulling the carbs, so may as well save yourself the trouble and check everything I listed.

[Rx_only]

Hello and thanks for the response! I can check 1,2 and 4 but beyond that is past what I can do at home. The person I bought it from said the carbs were recently cleaned but idk how reliable that was lol. Anyways I will try and ask a buddy to help me out with the other steps. I live in NY so it's still pretty darn cold here. Can't wait to get on the road this spring

[Dr.McNinja]

Hello and thanks for the response! I can check 1,2 and 4 but beyond that is past what I can do at home. The person I bought it from said the carbs were recently cleaned but idk how reliable that was lol. Anyways I will try and ask a buddy to help me out with the other steps. I live in NY so it's still pretty darn cold here. Can't wait to get on the road this spring

At 13k miles its likely worth it to look at your valve clearances anyway. At 22k miles my 06 GS500F only needed an exhaust shim change, everything else was in spec. If the PO didn't have proof of them being cleaned, I would clean them again to be certain. The worst thing that happens is you learn something about carbs at that point. Everything I listed is pretty easy if you have a manual, youtube, and some patience. Just take your time. Mechanical stuff is pretty easy.

[Rx_only]

Yes I plan on getting the valves checked if the carb is coming out anyways.
I do have a question about carb and fuel system cleaners you can buy at autozone or other places. Do those do a decent job compared to manually removing the carbs? I wouldn't assume so but just checking.
Thanks again for the help!

[Dr.McNinja]

Yes I plan on getting the valves checked if the carb is coming out anyways.
I do have a question about carb and fuel system cleaners you can buy at autozone or other places. Do those do a decent job compared to manually removing the carbs? I wouldn't assume so but just checking.
Thanks again for the help!

Nothing will beat tearing down the carbs and throwing all the bits in an ultrasonic cleaner. You might be able to get away with a fuel additive if the carbs aren't THAT bad but in general no, it won't help much at all.

[Rx_only]

Ok thanks!
I will try to figure this out over the weekend. I will also try playing with the idle screw if all the steps don't show results.I Rather leave the carbs on unless nothing helps.

[Dr.McNinja]

Ok thanks!
I will try to figure this out over the weekend. I will also try playing with the idle screw if all the steps don't show results.I Rather leave the carbs on unless nothing helps.

I'm going to be honest with you, playing with the idle screw will not help a hanging idle. When I bought my bike I had a hanging idle. The problem was a mix of carbs being gunked up beyond all belief, and poor stock jetting. The only thing that fixed it was a resync + rejet.

[Rx_only]

I know this varies from state to state but about how much does cleaning, synching and valve checks normally cost? I was told about $300
Money is tight with college costs 

[Atesz792]

I know this varies from state to state but about how much does cleaning, synching and valve checks normally cost? I was told about $300
Money is tight with college costs 

Dunno about you guys, but for that sum, I'd do it myself instead. Here it costs between 1/3 and 1/2 of that (equivalent in our local money).

[gsJack]

Hello, this is my first bike and after purchasing it and having it stored for a few months I realized after starting ang warming up the bike that it idles high once warmed up and it takes a while to return to idle after revved up. The idle starts normal but after warning up for 15 mins once I rev it the idle goes down slowly and hangs at about 3k. The throttle snaps back fast with a little play but not much.
A perfect example here (not my bike) http://youtu.be/obbaeDCFhFE
My bike had 13,700 miles. Any input would be awesome!

I've been wondering since this first post how you warmed it up, by riding it for 15 min or by it sitting and idling for 15 min? 

............I'm going to be honest with you, playing with the idle screw will not help a hanging idle. When I bought my bike I had a hanging idle. The problem was a mix of carbs being gunked up beyond all belief, and poor stock jetting. The only thing that fixed it was a resync + rejet.

My first GS500 was a 97 bought new in Mar 99, it had been sitting in the dealer's showroom for 2 years and they put in a new battery and cleaned the carbs, probably just ran some Gumout thru the carbs on running bike, and I headed home with temperature about 38F outside.  Thought I'd made a big mistake but by the time I got to hilly twisty River Road it was thoroughly warmed up and I then thought it felt like a sportbike compared to the 85 Nighthawk 650 I had ridden over to the dealers to trade in.

Come summer and very hot days I began to have a hanging idle, around 3k or so, and I attributed it to the lean jetting.  So when I pulled up to a stop I'd reach under and very slowly turn the idle speed down until it dropped off to normal 11-1200 rpm.  Repeated that several times and on a couple more occasions that summer and never had a hanging idle again on that GS  for the 80k miles I used it. 

The 02 I replaced the totalled 97 with had the 3 circuit carbs and never felt as lean as the 97 had, it's gone 100k miles on untouched carbs.  I don't mess with my carbs and they don't mess with me.  Riding year around here in NE Ohio the 97 really was too lean for the 20's and 30's, maybe even the 40's but I had an old CM400 I used for a winter bike when I had the 97 and the 02 I bought slightly used has been good for year around strictly stock.

[Dr.McNinja]

I know this varies from state to state but about how much does cleaning, synching and valve checks normally cost? I was told about $300
Money is tight with college costs 

Uhh, locally no one even looks at valves for under $500. Mostly because it's very, very slightly harder on most bikes (you have to remove the cams to replace them, which requires you to retime the bike and that intimidates people), bikes chassis are tight spaces, and mechanics in general just like to take you to the cleaners on everything. Carb cleaning here costs around $180 normally, ~2.5 hours of labor plus parts if you need gaskets and stuff.

Both jobs are incredibly easy on the GS. Even on newer bikes the jobs aren't that hard. There is literally nothing to be afraid of. Take your time, keep count of your parts, and you'll do fine. Carb cleaning usually doesn't require a complete tear down of the carbs (just the bowls, jets, needles, etc) so you don't have to deal with the throttle cable return springs flying everywhere, or getting everything back on the rails again.

Come summer and very hot days I began to have a hanging idle, around 3k or so, and I attributed it to the lean jetting.  So when I pulled up to a stop I'd reach under and very slowly turn the idle speed down until it dropped off to normal 11-1200 rpm.  Repeated that several times and on a couple more occasions that summer and never had a hanging idle again on that GS  for the 80k miles I used it. 

The 02 I replaced the totalled 97 with had the 3 circuit carbs and never felt as lean as the 97 had, it's gone 100k miles on untouched carbs.  I don't mess with my carbs and they don't mess with me.  Riding year around here in NE Ohio the 97 really was too lean for the 20's and 30's, maybe even the 40's but I had an old CM400 I used for a winter bike when I had the 97 and the 02 I bought slightly used has been good for year around strictly stock.

You probably don't need to touch the carbs if you use it enough to keep gas going through the bowls and the gas in your area is generally clean. When I got the bike the PO let it sit for "6 months", but the gunk in the carbs told me more like "3 years". It was absolutely necessary to clean and resync them. When I pulled my carbs most recently my bike had been sitting on bad gas for 3 or so months and the only jet that needed to be cleaned at all was my pilot jet, and that likely could have been take care of with a gas additive.

I just feel like playing with the idle adjustment is addressing the symptom and not fixing the actual problem. Especially if you know at one point it was configured correctly and now it's doing crazy stuff.

[gsJack]

Well I wouldn't consider making a simple idle speed adjustment a change in configuration.  I've adjusted my idle speed up in the fall and down in the spring to keep them at about the same speed year around which for me is usually about same as mfg spec.

Now on to valve adjustments on the GS.  If you have cold compression in both cylinders and the tappets aren't noisy when it's hot then the valves are not affecting the running of your engine.  You are OK for today and for many todays but not forever if you expect long life from your exhaust valves.

The Suzuki spec of .001-.003" clearance for intake valves is OK, I left mine set at this spec for 80k miles on my 97 and 100k miles on my current 02.  No intake valve shim changes were required on either bike.

The Suzuki spec of .001-.003" clearance for exhaust valves is too tight, it doesn't allow enough cooling seat time for the very hot exhaust valves and run at Suzuki's minimum spec they will recede into the seats over time.  A tight clearance of around .001" run for many miles on the tighter of the 2 exhaust valves on my 97 required constant shim changes and was down to a minimum 215 shim before 80k miles.  When the same pattern developed on my 02 at about 30k miles I started setting exhaust valves at a revised .003-005" gap and they went 10's of thousands of miles without shim changes with the wider gap.

http://img.photobucket.com/albums/v443/jcp8832/GSvalvelogs_zps55f27f5e.jpg
 

[Rx_only]

Hello, this is my first bike and after purchasing it and having it stored for a few months I realized after starting ang warming up the bike that it idles high once warmed up and it takes a while to return to idle after revved up. The idle starts normal but after warning up for 15 mins once I rev it the idle goes down slowly and hangs at about 3k. The throttle snaps back fast with a little play but not much.
A perfect example here (not my bike) http://youtu.be/obbaeDCFhFE
My bike had 13,700 miles. Any input would be awesome!

I've been wondering since this first post how you warmed it up, by riding it for 15 min or by it sitting and idling for 15 min? 

............I'm going to be honest with you, playing with the idle screw will not help a hanging idle. When I bought my bike I had a hanging idle. The problem was a mix of carbs being gunked up beyond all belief, and poor stock jetting. The only thing that fixed it was a resync + rejet.

My first GS500 was a 97 bought new in Mar 99, it had been sitting in the dealer's showroom for 2 years and they put in a new battery and cleaned the carbs, probably just ran some Gumout thru the carbs on running bike, and I headed home with temperature about 38F outside.  Thought I'd made a big mistake but by the time I got to hilly twisty River Road it was thoroughly warmed up and I then thought it felt like a sportbike compared to the 85 Nighthawk 650 I had ridden over to the dealers to trade in.

Come summer and very hot days I began to have a hanging idle, around 3k or so, and I attributed it to the lean jetting.  So when I pulled up to a stop I'd reach under and very slowly turn the idle speed down until it dropped off to normal 11-1200 rpm.  Repeated that several times and on a couple more occasions that summer and never had a hanging idle again on that GS  for the 80k miles I used it. 

The 02 I replaced the totalled 97 with had the 3 circuit carbs and never felt as lean as the 97 had, it's gone 100k miles on untouched carbs.  I don't mess with my carbs and they don't mess with me.  Riding year around here in NE Ohio the 97 really was too lean for the 20's and 30's, maybe even the 40's but I had an old CM400 I used for a winter bike when I had the 97 and the 02 I bought slightly used has been good for year around strictly stock.

I warmed it up standing at idle for 5 mins then occasionally gave it some throttle to get it fully warmed. I'm in NY so it's pretty cold here. I'm not sure if that affects the bike as much as what I'm explaining. The PO who sold it to me had it since April of 2014 and it was sitting for about a month or two nothing major. I have it sitting now for 2 months but I let it run for 15-20 minutes at idle with occasional throttle every single sunday.
How did you fix your problem? Did it go away on its own?

[Rx_only]

I might just try cleaning the carbs myself I look at some videos and it doesn't seem to hard. I couldn't however find a video for 2004+ versions. Does anyone have a link to a video on how to clean or disassemble the carbs for cleaning?
Thanks in advance!

[J_Walker]

I might just try cleaning the carbs myself I look at some videos and it doesn't seem to hard. I couldn't however find a video for 2004+ versions. Does anyone have a link to a video on how to clean or disassemble the carbs for cleaning?
Thanks in advance!

+04 is the easiest ones. just disconnect the throttle position sensor. and fuel line, and vacuum. and it comes apart. you shouldn't need to remove anything but the top diaphragm cover, and the bowl on the bottom.

[gsJack]

........................How did you fix your problem? Did it go away on its own?

I bought the 97 new in Mar 99 and by mid July it had 8k miles on it.  It was during a very hot spell of summer weather that the hanging idle first occurred and I managed to eliminate the problem by very carefully adjusting the idle speed.  After messing with it a few times over a brief period it was gone never to occur again. Starting the following year we began taking annual trips to the Aderondak(sp?) and Smoky Mtns running 400-500 mile interstate days at 75-85 mph indicated to get there and did some very hard riding in the mountains on some very hot days but the hanging idle problem never occurred again.  That 97 had 80k miles on it when it was replaced by the 02 in the fall of 03.

Could be cleaning your carbs and rejetting a bit richer will fix your problem, think most here would agree that's the way to go but I'd at least give it a good test ride on the road and that's why I asked how you were running it for 15 minutes.  Sitting in place and idling will heat up areas of an air cooled engine that riding them won't, would be starting to overheat it in warmer weather.

Good luck with the carb work I did my first carb back in '48 and many after that for autos so I don't tear into bike carbs unless I think it's absolutely necessary.     See your looking for a vid?  Only one I noticed was in the listing of vids at top of this section for 01 carbs, the GSs had 2 circuit carbs from 89-00 and the current 3 circuit ones from 01 to present, it might be helpful.

I agree there will be more problems with carbs that sit unused for long periods than ones that are used continuously but how long?  I think if they are not actually blocked they will clean up quickly when put back in service with the injector cleaners in modern gas.  That 97 I refer to sat for 3 months every winter while I splashed thru the salt water with the old CM400 and after it was replaced by the 02 it mostly sat in the garage for 3 years being started and used briefly only a few times.  Never felt the carbs had a problem on it.   

[Rx_only]

Thanks for the best wishes and help! I plan on riding as soon as it's not Antarctica cold here  in NY