Please Help GL1000 Carb Setup and Sync


Information and questions on GL1000 Goldwings (1975-1979)
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RattleRocket
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Please Help GL1000 Carb Setup and Sync

Post by RattleRocket »



We just picked up a super clean, low mile ‘79 Goldwing and we are trying to get it running right. I have meticulously rebuilt the carbs, adjusted valves, and picked up a 4-gauge vacuum sync tool. Didn’t mess with the previous sync settings during the carb build, and got it running (kinda rough), then tried to get it dialed in with the four sync vacuum gauges. I’m afraid I should have started with a better quality gauge set, because I’m only making it run worse. Probably ran the bike about four hours, trying to get it dialed in, to no avail! I ordered a set of oil filled vacuum gauges to make a better setup for the sync process.

Here’s my question-
Can someone please give me a decent initial setup procedure to get the carbs sync close before firing it up again? Has anyone used a feeler gauge to set the butterflies? Other suggestions?
Thanks!
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dingdong
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Re: Please Help GL1000 Carb Setup and Sync

Post by dingdong »

I usa a piece of heavy paper similar in weight to a business card about 1/4 in wide. Adjust #3 carb using the idle speed screw til you feel a slight pressure on the paper. Adjust #1 using the adjuster screw for that carb. Adjust #4 then finally #2. If done carefully all carb butterflys should be very closely matched. Then proceed to this How To. This is for an 1100 but the steps are identical.
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RattleRocket
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Re: Please Help GL1000 Carb Setup and Sync

Post by RattleRocket »

Thanks dingdong,
So you use the paper feeler gauge inside each of the sync adjusters?
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dingdong
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Re: Please Help GL1000 Carb Setup and Sync

Post by dingdong »

No. Sorry I wasn't more clear. Under the butterflys.
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ct1500
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Re: Please Help GL1000 Carb Setup and Sync

Post by ct1500 »

And I might add with a proper bench sync the engine should run fairly well out of the gate if engine compression, spark and carb rebuild are correct. If it does not run well by adjusting the idle speed and mixture screws then you need to revisit one of the three previous areas.
A vacuum sync is never a cure for a poor running engine after a bench sync. It is the icing on the cake that will take no more than 1/8-1/4 turn on sync screws to dial the engine in. Any defect in compression, spark quality and mixture settings will lower manifold vacuum gauge readings from optimum.
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RattleRocket
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Re: Please Help GL1000 Carb Setup and Sync

Post by RattleRocket »

Thanks a bunch!
I’ll work on the bike again next week.
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OldguyGlen
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Re: Please Help GL1000 Carb Setup and Sync

Post by OldguyGlen »

I used just a fine wire (twist tie with paper stripped off, they come in many diameters). I meticulously bench sync'd them, using same procedure as dingdong above. It ran so well that I've never bothered doing a vacuum sync. That was 3 yrs ago. It idles perfectly.
sickradsean
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Re: Please Help GL1000 Carb Setup and Sync

Post by sickradsean »

If you want to forego the feelers you can sight gauge the bench synch. There is an intake hole on the bottom of each carb breather just behind the butterfly. Eyeball it so you see the same amount of this hole on each carb. Should run decent from there, then you can do a gauge synch. OH! Also make sure your mixture screws are at stock specs. You can do an idle drop from there to even out the carbs.
RattleRocket
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Re: Please Help GL1000 Carb Setup and Sync

Post by RattleRocket »

Thanks sickradsean,
That’s how I first did a bench sync before installing the rebuilt carbs. Maybe I didn’t get them close enough as I “eyeballed” the butterflies to one of the bottom holes, but they were still off enough that I had a hard time syncing them with the gauges. And the ‘79 doesn’t have adjustable idle mixture screws, as they are factory set with little plastic caps. So I didn’t mess with them when I rebuilt the carbs.

After my first attempt to sync them failed, I did pull the intakes back off each carb and did the wire feeler setup on each butterfly. It worked best for me to use a very small wire about.030” diameter. That did the trick! It made a big difference, and the bike was able to idle down after warming up, so I was able to then use the vac gauges to dial them in perfectly.

Now I’m trying to chase a slight misfire issue. I wanted to keep the stock ignition, rather than convert to the Dyna electronic unit. So I installed new points and condenser, adjusted both points, and also set them to their respective timing marks. In that process, I first set the static timing with a test light. Then I picked up the little timing sight glass to check the timing with a strobe light. That’s when I noticed that I still have random misfires on each plug. I cleaned and rechecked the points, and it runs pretty good, but still see misfires! So I bought a new set of Dyna coils and plug wires. I’ll be installing those this weekend, to hopefully fix that problem.
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Re: Please Help GL1000 Carb Setup and Sync

Post by Old Fogey »



'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!

( Seriously, you haven't read all 115 pages of my http://www.wingovations.com website ?? :shock: )
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