1980 GS1100E: Can't keep her running

[rustybronco]

Sounds like the bike needs maintenance. It's very hard to diagnose running problems if the maintenance is not up to date. Clean carbs, fresh carb O-rings, properly adjusted pilot screws, vacuum sync, check coil voltage, verify carb jetting is correct though plug chops, etc. Bikes more than 30 years old and needs some TLC.

Your answer lies here.

[Steve]

Agemax,
I have a screw in the tube.

From the looks of that picture, it appears that your screw is in the VENT tube, not the VACUUM tube.

The VACUUM tube in question is the one that goes from the top of the outlet of carb #2 over to the petcock.
You can see the open port here, just inside the bend of the "choke" linkage:


The tube where you apparently have a screw stuffed in should be OPEN, so the float bowl can breathe.

.

[bluehwy]

MEK the carbs?

[bluehwy]

I know it's a weird picture. I had to shove the camera under the carbs to see it. It's the line coming off the #2 carb but it lays down over the top. What you see is it hanging down over the top between carbs 1&2.

[Steve]

OK, it just looks like it's in the same position that the vent tube would be in.

As long as the screw is reasonably tight in there, you should not need any sealer.

.

[bluehwy]

I can't see the vent tube though. I guess I'm going to have to start pulling it apart...

[bluehwy]

This is the tube I have plugged.

[bluehwy]

tear down of carbs

Well, I pulled the rack off. I took pics along the way so that I can try and diagnose any thing that may be a contributing factor. I'll try and post pictures because I already see things I don't understand but don't look right.

[Maddevill]

If it will run with the choke on and stops with the choke off your pilot jets are PLUGGED. Possibly the passages as well. if that mechanic did not remove ALL the jets and clean them and the passages he did not "clean" your carbs.

[FLHGSRay]

Go through the carb rebuild ENTIRELY. Don't skip a thing, and make sure all of your jets and needles match. Don't just soak the carbs. Soak them for at least 24 hrs, then blow air through all the passages to clear them. Get good quality o-rings from the o-ring guy here. Remove the boots also, and replace the o-rings, even if you're convinced they're not leaking. Don't mess with the ebay stuff. If you do all this properly, then the bike still doesn't run right, at least you'll know what it ISN'T. If you skip even one step, then the carbs will always be in question.

[bluehwy]

Thanks, I was always skeptical that he did a thorough job. It makes sense that fuel is not passing all the way through. I have pictures but I don't know how to get them up. I was hoping to have an external link like dropbox with a folder but I don't know how to allow access to it...

[bluehwy]

FLHGSRAY, I am with you 100%. I will dive right in...

[bluehwy]

If it will run with the choke on and stops with the choke off your pilot jets are PLUGGED. Possibly the passages as well. if that mechanic did not remove ALL the jets and clean them and the passages he did not "clean" your carbs.

I won't say the name of the shop but after numerous complaints, including a loose wheel after a tire change, I never went back.

[bluehwy]

pre dismantle

There's fuel on the outside of #1?

[bluehwy]

inside of #1 and #4

#2 is not as bad as #1 and #3&#4 are clean?