83 Gs550e Won't Idle

[GQROD]

83 gs550e, FULL choke bike runs at 3000 rpm until warm, petcock on prime. Slowly dies won't idle. Will start if i BLIP the throttle but will die once i stop giving throttle.

Any help would be greatly appreciated i have been working on this bike for a month and a half and through the help of those here i have gotten this far with no major problems. Thank you in advance for you help.

Below are all the things i have done so far.

1-Chem dipped carbs-Berryman's
2-Blew out and ensured ALL orifices were clean.
3-Replaced ALL jets, mains, pilots, air jets to stock specs per factory manual.
4-Stock Air Box
5-Stock mufflers
6- Reset floats to stock specs as per manual between 20.5 mm +/- 1 mm using vernier caliper. ( gasket removed ).
7-Battery Brand New Fully Charged.
8-VALVES ADJUSTED TO -ZERO POINT THIRTEEN MM " 0.13 " -not yelling just correcting the error in posting.
9- Plugs cleaned gapped to 28 thousandths-DE8 hot plug. NGK
10-Bench Synced carbs, awaiting Carb Sync tool in mail from England.
11-NEW INTAKE MANIFOLD O-RINGS-OEM
12-NEW air filter stock, cleaned out inside of air box.
13-MIXTURE screws set to 1 1/2 turns out -will not start any other way.
14-Plugs are not wet, NOT black or sooty. Appear clean.
15-Increasing idle speed adjustment screw out does not help!
16-Bowls are full of fuel.

[MelodicMetalGod]

GQROD,

Your issue sounds very similar to what my bike had when it first came to me. To address the issue I did the following:

1) Replaced air filter
2) Replaced spark plugs
3) Cleaned and rebuilt carbs

Although those things were all good things to do and I would recommend that any new owner of a GS do them straight away, the thing that turned out to be the real culprit was.... (wait for it)....

Replacing the O-Rings between the carb boots and engine.

I'd rec'd the advice from many members that this was the most likely cause for the issue and I'd even tested for a leak in the air system using the "WD-40" spray test, which revealed nothing. After further research and advice from the GSR members, I decided to replace the boots and o-rings just to eliminate them from the list of possible issues. The old boots weren't in bad shape at all but the o-rings were definitely flattened out a bit. Once the new stuff was installed...voila! No more hard starting, no more high idle after warm up!

Best of luck!

[GQROD]

I replaced the intake manifold o-rings with new ones from suzuki, thank you so much for your help i appreciate that i am not going crazy trying to figure this out.

[chef1366]

The 13mm valve clearance could be a problem.:-D

[GQROD]

I adjusted them to 13mm because those on the forum and the factory manual say loose is better so i went to the maximum that was safe, however as an aside i did mange to get it running and idling. I pulled the plugs after getting it running with the throttle holding the rpms at 2000, they were all black and sooty, i adjusted the mixture screws to 1 1/2 turns out again and while holding the throttle adjusted the idle speed screw while the pet cock was in teh prime position, FINALLY GOT IT TO IDLE. It held the idle for a good while however i may have to check the pet cock again. It seems it must be on prime until it warms up fully then change to the ON position and get off the choke. I hope once i sync them and adjust the mixture for each cylinder with the COLORTUNE tool these problems will vanish. Thank you to all for your advice.

[MelodicMetalGod]

I adjusted them to 13mm because those on the forum and the factory manual say loose is better so i went to the maximum that was safe, however as an aside i did mange to get it running and idling. I pulled the plugs after getting it running with the throttle holding the rpms at 2000, they were all black and sooty, i adjusted the mixture screws to 1 1/2 turns out again and while holding the throttle adjusted the idle speed screw while the pet cock was in teh prime position, FINALLY GOT IT TO IDLE. It held the idle for a good while however i may have to check the pet cock again. It seems it must be on prime until it warms up fully then change to the ON position and get off the choke. I hope once i sync them and adjust the mixture for each cylinder with the COLORTUNE tool these problems will vanish. Thank you to all for your advice.

I believe that chef1366 was making a joke...the max valve clearance spec is .13 mm (you wrote 13 mm, although I'm quite sure that you simply assumed the decimal point).

You shouldn't have to have the petcock in the prime position...when the bike is running, on s/b fine UNLESS there is a problem with the vacuum circuit in the carbs or the line from the carbs to petcock or with the petcock itself.

Your plugs have probably been affected by using the throttle to achieve idle. Here's a handy reference for spark plug reading: DansMC.com

If you're holding the throttle open and adjusting the set screw to extreme, it would seem that you're having a problem with the idle circuit in the carbs.

Questions:
1) What idle RPM did you achieve?
2) How far did you have to adjust the idle set screw?
3) You mentioned it "held idle for a good while". When and why did it lose idle?

[GQROD]

I believe that chef1366 was making a joke...the max valve clearance spec is .13 mm (you wrote 13 mm, although I'm quite sure that you simply assumed the decimal point).

You shouldn't have to have the petcock in the prime position...when the bike is running, on s/b fine UNLESS there is a problem with the vacuum circuit in the carbs or the line from the carbs to petcock or with the petcock itself.

Your plugs have probably been affected by using the throttle to achieve idle. Here's a handy reference for spark plug reading: DansMC.com

If you're holding the throttle open and adjusting the set screw to extreme, it would seem that you're having a problem with the idle circuit in the carbs.

Questions:
1) What idle RPM did you achieve?
2) How far did you have to adjust the idle set screw?
3) You mentioned it "held idle for a good while". When and why did it lose idle?

Yes i took it as such that it was a joke but my sense of humor has waned in attempting to achieve a steady idle which i have. But yes in my haste let out the decimal.

Since my last post i was able to take it out for a spin because the idle held after adjusting the idle screw. It did quit on me while coming to a stop but it started with a throttle blip and off i went.

1- I ahieved 3000 rpm full choke
2- I would say an 1/8th of an inch to get it to idle at 1200 rpm more when i took it out for a test drive.
3- It lost idle with no choke after about 5 mins.
4- I believe that once they are synced with the carbtune and the individual cylinder mixtures tuned with the color tune it should run better.

I replaced ALL the jets with new ones- OEM, however your advice makes sense and i will double check my settings and verify that everything is where it should be set to, Thank you for your patience and your help, i sincerely appreciate it.

[MelodicMetalGod]

1- I ahieved 3000 rpm full choke
2- I would say an 1/8th of an inch to get it to idle at 1200 rpm more when i took it out for a test drive.
3- It lost idle with no choke after about 5 mins.
4- I believe that once they are synced with the carbtune and the individual cylinder mixtures tuned with the color tune it should run better.

I replaced ALL the jets with new ones- OEM, however your advice makes sense and i will double check my settings and verify that everything is where it should be set to, Thank you for your patience and your help, i sincerely appreciate it.

3000 rpm is, of course, a bit high (my bike idles well under 2000 while on choke). Sounds like the idle set screw adjustment isn't extreme. So it seems that there are two symptoms (please confirm or correct):

1) High warm up idle (3000 RPM)
2) Inability to maintain idle w/o stalling after warmup

If that's correct, then balancing and synching the carbs may very well help and will need to be done regrdless. However, I would think it more likely that you have a clog somewhere in the idle circuit (see the FSM page 4-6) preventing sufficient fuel reaching the cylinders at idle, and/or have an air leak that is preventing sufficient vacuum from pulling enough fuel into/through carbs and/or have a suspect choke operation (which could explain the issues on both circuits.

FYI: I'm not an expert on this stuff, but I have had to deal with the fuel delivery on my bike more than anything else. Clogged air jets, clogged fuel jets and air leaks are the main issues that cause most issues of this nature.

[TheCafeKid]

I adjusted them to 13mm because those on the forum and the factory manual say loose is better so i went to the maximum that was safe, however as an aside i did mange to get it running and idling. I pulled the plugs after getting it running with the throttle holding the rpms at 2000, they were all black and sooty, i adjusted the mixture screws to 1 1/2 turns out again and while holding the throttle adjusted the idle speed screw while the pet cock was in teh prime position, FINALLY GOT IT TO IDLE. It held the idle for a good while however i may have to check the pet cock again. It seems it must be on prime until it warms up fully then change to the ON position and get off the choke. I hope once i sync them and adjust the mixture for each cylinder with the COLORTUNE tool these problems will vanish. Thank you to all for your advice.

13mm? or .13mm?? MASSIVE difference. I dont know what the correct clearance is on your particular bike, but, something tells me that THIRTEEN (yes 13) WHOLE millimeteres is a bit excessive. I have a feeling however if the clearance was actually that large, the bike wouldnt have started, and if it did, probably would have grenaded on start up...

[GQROD]

" 0.13 " MM SORRY FOR THE CONFUSION- not yelling at anyone trying to help just clarifying this and yes grenaded is an understatement ( very funny though ) I realize there is a huge difference in the measurements my math teacher would never have forgiven me, now onto the progress report

1-finally got the carbtune 2 in the mail.
2-balanced the carbs
3- during adjustment idle was surging.
4- throttle blips show serious BOGGING down during throttle up.
5- runs strong mid-range and top end
6- shuts off at stop signs, won't start without throttle blip.
7- pulled plugs and they are VERY RICH.
8- i'm ordering the colortune tool to hopefully resolve this mixture problem,
9-currently mixture screws set at 1 1/2 turns out from lightly seated as recommended by forum and factory manual.
10- i'm suspecting also the petcock may possibly be a culprit so i may order a new one if i see that it's not functioning properly.
11-Thank you sincerely to all of you for your advice and help i do appreciate it.
12-yes you are right it was 3000 rpms on warm up full choke however adjusting the choke resolved this so it's in the 2000 rpm now.

[chef1366]

What's your compression numbers?
Do you have a manual? Check out the ignition parts. What's your voltage at the battery and the coils.