Idle issue.

[alstensby]

I'm guessing I just need to let it work itself out, but wanted to make sure. I have an '82 GS650GL that I've salvaged out of my neighbors garage. I hadn't run since late '02. So, as far as the engine is concerned, I haven't had to do too terribly much to get her running. I pulled the plugs and replaced them, redid the valve cover gaskets and stripped and dipped the carbs. Keep in mind, I'm not a mechanical wiz so I stripped down the carbs as far as I could go without digging in to it too much. That means opened it up, pulled plugs and jets, etc. Anyhow, I put everything back together and got her to start up and ride. The issue I'm noticing is that the idling isn't consistent until it's REALLY warmed up, then she idles pretty good. If it hasn't warmed up for a long time and I'm riding it around to check everything out, I can pull in the clutch and get one of three results:

-RPM jumps to about 4rpm
-RPM drops to normal idle
-She dies

Soooooooo...WTF? Do I just need to really keep her warmed up big time? Is there probably just a few things in there that need to be worked out from sitting? I have a can of Sea Foam and haven't had a chance to put much time on it (about a mile) since the bars are bent and I haven't picked up the "new" ones yet. Any input is appreciated.

[Steve]

Keep in mind, I'm not a mechanical wiz so I stripped down the carbs as far as I could go without digging in to it too much.

If you only went in to your 'comfort level', you probably did not go far enough. Did you follow the carb cleaning series? Wonderful write-up with good illustrations. If you did not take the carbs completely apart, there is a good chance that you have destroyed some o-rings. A good place to get your o-rings is from cycle o-rings.com. The proprieter there is a member of this board. Click on the link, you are interested in items 1 and 3. Install them in your bike, do all the adjustments and you should be good to go.


.

[alstensby]

Summmmmmmmmmmmmmmmbich.

[spyug]

The complete cleaning and rebuilding is definitely the way to go. While you're waiting for parts to come in, try running a tank or two through with Seafoam.

If you have done a partial cleaning the Seafoam might help clean out the rest of the crud.

Once you have rebuilt the carbs you will need to set the airfuel mixture and synch them to achieve proper idle and balance. As mentioned, read the threads and tutorials on the site.

As carbs are only one part of the fuel delivery system, you should also check over the tank, petcock and fuel lines for rust and cruds ( solidified gas). Tanks often get rusty and this leads to particles in suspension that can clog petcocks, fuel filters, lines and carb jets. Rusty tanks need cleaning and sealing. You can clean light rust in a tank with household vinegar. Pull the petcock and sender unit if fixed and make covers from scrap plastic. Smear on some silicon and screw the covers in place. Fill the tank with vinegar and let it sit for a few days. If the tank is heavily rusted repeat a couple of times. Pour off the vinegar through a coffe filter to remove the rust particles and reuse. To help tougher scale add some nuts and bolts or length of chain and swish things around.

If there is a lot of rust you should consider sealing the tank with Kreem, POR-15 or Redkote. It will encapsulate the remaining rust and plug any pinholes that may start developing. I've used both Kreem and POR and they both work well but follow the instructions very closely. I can't get the Redkote here but I've been told it is far superior to anything else.

You can do all of this in stages but for peace of mind they should all be done at some point...maybe after riding season.

Let us know how you make out .
Cheers,
Spyug

[babcockdonald]

Not sure about how these bikes are set up anymore as I sold my GS last year. But, most bikes that I know of have rubber intake manifolds between the carbs and the engine. Check these for weather cracks. If the cracks are bad enough it will cause a vacuum leak and the bike will run like crud. You could have some cracks in them that aren't to bad and they could be sealing themselves back off once things get hot.

You can check these visually and if you see cracks you can spray them with carb cleaner when the bike is running cold and see if the idle changes. If it does then you have a vacuum leak around the last area that you sprayed.

Not sure if this will help you or not, because I can't remember how the carbs are on these bikes, but it is just a good troubleshooting technique as the rubber boots will eventually get stress cracks in them and cause problems.

[tconroy]

If you set your idle when it was warmed up chances are you have bad 0-rings where the intake boot manifolds connect to the engine.They are cheap and should be replaced.After the bike warms up it will idle high when these are bad and setting the idle when it is warm will cause it to die when it is not fully warm.Check your intake boot also for cracks and for leaks first.