New bike idles but won't rev when cold, just bogs and when warm it has a hanging idle. Sprayed all over around intake and carbs for vacuum leaks. But found nothing. Have removed and capped all emissions equipment hoping that there was a vacuum leak there but still nothing. Pulled vacuum operated petcock and replaced with single in and out. Capped other nipple at tank. Plenty of gas in tank as well.

BACKSTORY
After searching and reading through all the Carb related posts on here, and trying just about everything that was suggested in them, I still am having trouble getting the bike to.run properly. I even went through the thread on jets (should be a sticky) to see what others are running.... I picked up a 2002 GS500 that wasn't running because it needed some fuel lines. Though it would start on ether. No bad noises from the engine etc... because it had sat, I pulled the carbs and tank and cleaned them both out, with help from threads on here. Jetting is set at stock for pilot and mids but main is set to 130 instead of 127.5. I have boiled the carbs and cleaned the bowls and passages with carb cleaner as well as the boiling. Brought the carbs to the local shop and had them reset everything all settings to stock including pilot screw and float levels. But the problem is still there. Wondering what the next step should be. Any help would be appreciated.

did you check the valve clearances?

Have you done a compression test?

Is it running on both cylinders? sounds kind of like Trey when he was running on mostly one cylinder due to a bad spark plug. Try swapping plugs. Pull one wire - what happens? Pull the other one and what happens? Ant difference between running left only and right only? Getting good spark on both sides?

^^ that too.

I just got an 06 gs500f and i'm having the same problem. I start the bike on full choke and let it warm up. After that I take the choke off. After that if will randomly rev itself up to around 5k for no reason. and sometimes when I get off the throttle to slow down it takes awhile for it to rev down. I haven't done any mods to the bike. Person I bought it from said it had been sitting awhile so i'm guessing the carb is gummed up or something 

Thanks for all the quick replies. I did a compression test as that seemed easier than checking the valve clearances. I got 63 psi on one cylinder and the compression went up to 140ish when i added a bit of oil through the plug hole. So it appears a rebuild is in my future. Unless Im missing something. Should I bother checking the valve clearances?

Do a hot compression test, and check valves too, anyway 63 is low, but hot compression is what counts. Eventually it will get hot.
Cool.
Buddha.

anyone know of a rebuild kit that would be available for this bike? As its called in the automotive world, a re-ring kit?

For carbs try parts'n'more for pre-2001 carbs. I'm not sure they stock bits for the newer 3-jet carbs though. Maybe call them and see if they can help you find a source. I've used their carb kits and gasket kits and quality is excellent.

For piston rings, the best source is Suzuki original.

For gaskets probably Suzuki again for head and base gaskets if that is all you are doing, otherwise the parts'n'more gasket kit for a total rebuild situation.

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Check all your O-rings in the carbs and replace them if necessary, then make sure your using fresh non contaiminated fuel.

Had a local shop do a checkup on the carbs, then i rechecked compression on the engine while warm and without carbs to remove them from the equation. The pressures were still low. So, Ive torn the motor down. Surprisingly, it took less then an hour and a half to pull the cylinder heads. And it was a little fun to be honest. Bet you never thought youd hear someone say that. I do have a question though, according to the service manual, when i reinstall everything, in order to make sure the cams are in the right position i have to line up the RT on the left side coil. But it doesnt say which piston should be on top dead center. Correct me if Im wrong, but the mark will line up twice and only one of those two revolutions will be correct.

Check out the top end re build videos in the turtorial section. 

I am having the same issues with  my new 02 gs that has trouble staring up and will not hold an idle (a pathetic idle at that) until very hot. I checked the carbs and all the jets were spotless. I checked the valves clearance today and the exhaust valves and had no clearance. I betting that when i swap em out for thinner shims that I'll be g2g.

Quote from: slipperymongoose on March 20, 2012, 07:27:32 PM
Check out the top end re build videos in the turtorial section. 

Totally forgot about those. Damn she makes it look so easy in the top end rebuild videos. Thanks!!

Could be slightly distracting too lol