Running WAY too rich.

[cheezeweezle]

I have spent a good deal of time lurking here and reading as much as I can, I finally joined so I could post.

I have a 1980 gs850. When I got it the darned thing would not hold an idle. I finally figured out that while it seemed to be running fine it was misfiring on #1. All the plugs had a good deal of carbon fouling and were wet with gas when I removed them. I put new plugs in and it starts right up and runs just fine.

My question is why are all the plugs that wet with gas? I assume I am going to gave to rebuild the carbs, but I have never worked on a carb in my life. Any other reasons I am overlooking?

[hikermikem]

First off, welcome to our forum - Cliff will be along soon to roll out the welcome mat...

Only way to sort out these old bikes is to methodically complete all the maintenence items that most likely have been neglected for many, many years - especially if you know little to nothing about the bikes history.

Completely disassemble & clean (dip) the carbs...

New o-rings in the carbs & intakes...

Seal ALL air leaks (intake boots, airbox)...

Adjust the valves...

Check the electrical system, particularly voltage at the coils...

Then, you can begin to figure out where your issues are (if any remain).

Good luck, you can do it - it sounds difficult, but it's not that bad. Plus we are here to assist you along the way.

[mike_of_bbg]

Check your coil secondaries, they should be about 25k-35k ohms between 1 & 4 and 2 & 3, respectively. If it's really high remove the boots (they screw off the wires) and check them. Check the voltage reaching your coils and make sure it's at least 10V. Incomplete combustion can cause the plugs to be wet with gas.

I don't usually think of dirty carbs for rich conditions. Rather, clogged passages normally cause lean conditions. Cleaning carbs usually doesn't hurt though (other than time) and there's a good guide here. You could also check the jets and see if they're the correct size. Make sure none of your choke plungers are sticking. Float height plays a big part in mixture as well.

Check your air filter and make sure it's not over-oiled. It should be VERY lightly oiled. If there's too much oil it's going to choke and cause a rich condition.

[cheezeweezle]

I removed the new plugs after the bike has set without running for several hours. The number 1, 2, and 3 plugs are all still wet, number 4 is bone dry. Is there something that would cause gas to run into the bores while it's just sitting?

[Nessism]

Please read Mike's post again then read the info in this link...http://www.thegsresources.com/_forum...d.php?t=171846

[mike_of_bbg]

It's not unusual on these old GSes to have multiple issues all staring you in the face. My initial thinking would be an ignition issue plus perhaps a #4 carb in need of cleaning. Maybe the #4 exhaust valve was open and that fuel got to evaporate? Check your petcock, too, and make sure it's operating normally. As in, no fuel should be flowing out of it when the bike is not running. If fuel is running when the bike is off, the needle valves can have difficulties holding it back and it would end up overflowing the bowls. With the bike on the side stand that would favor the left-hand cylinders. Most normally though that would leak into the airbox. Plus your bike should only have one (maybe two if it stopped just right - when were the valve clearances last checked?) intake valve open at a time to leak into the cylinders. You could be leaking fuel down the petcock vacuum port, but that should only affect cylinder #2.

There are lots of possibilities here. Check some of the easy stuff first (like ignition, petcock), fix them, and move on to the next issue or possibility. Even with perfectly clean, spotless carbs you're not going to run well with an over-oiled filter, coils only getting 8V, or plug caps putting up hundreds of kohms of resistance.

Of the "top 10 GS issues" I've had to fix just about every single one of them. These old bikes will still run with a lot wrong with them. Great, reliable running takes work.

I removed the new plugs after the bike has set without running for several hours. The number 1, 2, and 3 plugs are all still wet, number 4 is bone dry. Is there something that would cause gas to run into the bores while it's just sitting?

[rustybronco]

These old bikes will still run with a lot wrong with them. Great, reliable running takes work.

That's worth making a signature line out of.

[wacky941]

I had a very similar problem with mine, the point at which I absolutely knew that I had a major problem was one night I started the bike and let it sit there idling for a couple minutes, getting ready to leave I turned the driveway lights off and when I looked at the bike the pipes were glowing red. I stopped riding it until I could figure out what was going on.

I finally took it to a local shop and in the end it turns out that the previous owner or whoever he took it to to have the carbs cleaned and rejetted (I'm assuming) did not have a clue what they were doing, the jets were all wrong!
When I dropped the bike off I had told him I needed the carbs cleaned and adjusted and to check and adjust the valves.

The first thing he asked when I went to pick it up was if I had done anything to the carbs then he asked if I had problems with getting the bike to idle properly, no to the first question and yes to the second question.
The PO had installed jets that were way oversized which caused all the same indications you noted, not to mention turned my pipes purple.

Now it runs EXCELLENT and purrs like a kitten! And the pipes no longer GLOW!

Yours might turn out to be a different problem but that's what fixed mine.

[cheezeweezle]

So i cleaned the carbs, the PO had set the floats at .35 inches instead of the recomended .88. I put everything back together and installed fhem today. I also cleaned the air filter, (k&n), and checked all the intake boots and airbox boots. Everything seems good to go.

When i began to set the air fuel mix using the highest idle method things got a little weird for me. I set all the air screws at two turns out from bottom. I started with the number 1 carb and as I turned it in the rpm's began to increase. it continued to increase as the air screw bottomed out. I adjusted the idle back to 900 rpm and continued to set the rest of the air screws. None of them came close to being set all the way to the bottom. I think they are all at around 1 to 1.5 turns out from bottom. I cannot smell gas anymore while it is running but i am now getting some light white smoke from the right exhaust that wasn't there before.

My questions are:
1: Is it normal for an air mix screw to be set all the way to the bottom? If not, how do i fix that?

2: This is my first experience with carbs, could the light white smoke be related to the fact that the bike sat for a couple of months without running, or is there possibly something more sinister lurking in there somewhere?

[gearhead13]

Have you checked the petcock for correct operation? With the petcock in the 'on' position no fuel should flow unless there is a vacuum applied to the smaller nipple, as the engine does when running.
Were the carbs completely dissasembled, dipped with new o-rings? If not, you are chasing your tail.

[cheezeweezle]

Yeah, I did it up all proper. I dug around till I found one of bassclif's mega welcomes and downloaded all sorts of stuff that kept me busy for a month. The petcock is working normally. The only thing that confuses me is that the air screw on number one has to be turned in all the way. It just seems weird to me.

[gearhead13]

I would check and set valve lash if needed for my next step. Maybe do a compression test to see how your valves are sealing.
Personally, I set all my mixture screws to the same turns out. If your valves are set properly and your compression is even you shouldnt have to have one carb set differently than the others. All four should require the exact same mixture, if they dont there is a problem somewhere else.