Rough Idle-even after many adjustments

[styxer]

Hi All,
I recently got a 650gld. The bike won't idle right. I have to constantly adjust the adjuster screw on the carb. For example: today I started the bike with the choke until warm. I went to take a test ride and when I got to the top of my driveway (as it slopes down where I work on it) and instantly after leveling off it reved up to about 3.5k. I sent the screw down a little and rode around the block. Just as I aproached the last stop sign the bike nearly stalls. I know it should run about 1k, but when its set that low it near stalls. I haven't adjusted the air screws yet (cause i have to drill out the screw cover apparently), but I'm outta ideas. ----I also am about to change the reg/rec cause it runs completley off the battery...so could low voltage also affect this. Thanks so much!! The book helps, but doesn't allways cure.

[mark]

I think we need a little more info. here.

What year is your bike? Is it all stock or has it been modified in some way?

What's the history? Have the carbs been cleaned, adjusted, or synchronized? You say "many adjustments"...what adjustments did you make? Did the bike sit for a while? How does the bike run when you ride it? Any popping, missing or "bogging" , or is this only an idle problem?

I assume you have good spark at the plugs? Pull the plugs and give us a read on the color. Should be light brown or tan.

[styxer]

Its an '83 all stock, and the guy I bought if from has used it for 4 yrs, 3 seasons. I just cleaned the carbs and jet but not synched. As for the adjustments, I had to replace the adjustment screw cause the plate was stripped (had to tap), new plugs, oil swap x/filter. It has been running for a month but not smooth. I guess it was only a few adjmnts, seemed like more. It runs fine when I'm on the road, except when at a stop in neutral or with clutch. I ran the ignition advance test and had cylinder 4 fire when contacted with the multimeter but no spark from the 3rd on disconect. I also ran a test for the stator and had high level for two wires but one was a little low. I'm assuming its close enough and might be the reg/rec which i ordered since it has charging problems. hopefully with the new reg/rec the electrical output will be higher. And by the way, YOU ARE AWSOME!! I didn't even think I would get a response (new to the forum thing)

[tconroy]

Its an '83 all stock, and the guy I bought if from has used it for 4 yrs, 3 seasons. I just cleaned the carbs and jet but not synched. As for the adjustments, I had to replace the adjustment screw cause the plate was stripped (had to tap), new plugs, oil swap x/filter. It has been running for a month but not smooth. I guess it was only a few adjmnts, seemed like more. It runs fine when I'm on the road, except when at a stop in neutral or with clutch. I ran the ignition advance test and had cylinder 4 fire when contacted with the multimeter but no spark from the 3rd on disconect. I also ran a test for the stator and had high level for two wires but one was a little low. I'm assuming its close enough and might be the reg/rec which i ordered since it has charging problems. hopefully with the new reg/rec the electrical output will be higher. And by the way, YOU ARE AWSOME!! I didn't even think I would get a response (new to the forum thing)

Your reg/rec probably is not the problem on idle.Mine was just overcharging and had no signs of idleing issues.I just had to add distilled water every 200 miles,but the new reg/rec fixed that. I have an83 gs 650 also and your problem might be dirty air filter and bad intake o-rings or intake boots leaking air.I had the same problem and have replaced all the above.Also check your sync screws on your intake boots they can leak and cause bad idle.Use wd 40 or water mist and spray around the boots and intake to check for leaks.Clean all your connectors especially the ones on your coils to the plugs and check your lug boots and regap your plugs then see what happens.Did your replace all the o-rings in the carbs?There are plenty of people on here that are ready to help you any way they can so keep us informed of your progress and we'll get ya running good in no time!

[mark]

Ditto the above post. It sounds like a vacuum leak or gunked up carbs to me. What do you mean when you say you "cleaned" the carbs. Did you separate them completely from the rack, take out the jets etc. and soak them, blow out passages etc.?

There's a great file on rebuilding carbs here on the site: http://www.thegsresources.com/gs_carbrebuild.htm . Manifold O-rings aren't that hard either. You'll have to find a synchronizer as well. Let us know how it goes.

[styxer]

I took out the carbs and worked on them as a unit. I took each one apart and sprayed the main jets with choke cleaner. Though....when I pulled the bowls off i noticed the book says to take the o-rings off the main jet.....either they are invisible, or some joker didn't put them back in! Anyway those and the needle jets where the only "Jets" I cleaned cause I didn't want to damage the pilot jets because it wasn't budging and I also didn't know about the jet needle. Are those components the essence of carb cleaning? The book doesn't really clarify on what to clean, just how to take 'em apart.

[tconroy]

I took out the carbs and worked on them as a unit. I took each one apart and sprayed the main jets with choke cleaner. Though....when I pulled the bowls off i noticed the book says to take the o-rings off the main jet.....either they are invisible, or some joker didn't put them back in! Anyway those and the needle jets where the only "Jets" I cleaned cause I didn't want to damage the pilot jets because it wasn't budging and I also didn't know about the jet needle. Are those components the essence of carb cleaning? The book doesn't really clarify on what to clean, just how to take 'em apart.

You need o-rings for the carbs and start over or replace them.Go to the main web page and on the left at the bootm you will find the carb cleaning section.The missing o-ring could be your only problem on the idle but do check the other things I have listed!

[styxer]

Thanks guys, I ordered a partial rebuild kit with O-rings, main jet and gaskets from Oldbikebarn.com. I will let you know how it runs after the rejuvination!

[Road_Clam]

Thanks guys, I ordered a partial rebuild kit with O-rings, main jet and gaskets from Oldbikebarn.com. I will let you know how it runs after the rejuvination!

I would HIGHLY advise you take the stripped carbs to a dealer and have them "dip" the carbs in cleaner solution. If there ever was water in the fuel, or just dirt in generall, 75% of the time the pilot circut gets plugged deep down inside the passage ways that you simply cant reach with carb cleaner. I work for a dealer and we have a special tank of carb cleaner. Dip the carbs for about 8 hours, and they come out looking brand new!

[mark]

I agree that in order to truly clean them that they need to be completely separated, soaked, blown dry with compressed air etc. Spraying carb cleaner on them or through the passages is a gamble.

A dealer can do it I'm sure, but I (and many others here) soaked mine in Berryman's that you can get at Autozone. Its nasty stuff, you need plenty of ventilation, but it comes with a little rack that you can put your pieces on and when they are done they are absolutely clean when blown dry with compressed air.

[styxer]

Well its been a while since I got back to this thread. Since then I changed the reg/rec, stator, clutch and choke cable and more. She runs reliably now. Though I guess I will bring it in to get the carbs cleaned, and synched since I just don't have the time (moving apartments). I tried adjusting the air screws which I drilled open but it did almost nothing. They mus be gummed to the max. So this is a "HELL YA!!!" to all you helping me become a first time rider. Also am taking the safety course this weekend! Thanks to you all....ride on!