Carbs

[Bob Shaw]

I been trying to sync the carbs on my 1982 gs850g. It was running but not well. Now it won't run at all. I tried adjusting the 3 screws with no luck. I then screwed them all the way down and started backing out 1/2 turn and tried to start the bike. No good. Are there any suggestion on how adjust these carbs. All help and suggestions are welcome. Thanks

[Nessism]

Turning all the screws down like you mention is just going to mess you up. You should set all the adjusters to the middle of their range and start over.

You need to sync 2 - 3 first and get the levels equal by adjusting the sync screw in the middle of the rack. Did you try that? Were you able to get the two equal? After those two are equal then you can then work to bring the outside carbs (1 & 4) to match 2 & 3. It doesn't matter which order. Sometimes adjusting 4 or 1 messed up the 2-3 sync for some reason but it shouldn't move much.

[Steve]

OK, let's back off a bit and get some background.

1. Have the carbs been off the bike recently?
1a. If they have, did you do a bench sync?
1b. Either way, get ready to take them off and DO a bench sync.

2. What gauges are you using to do your sync?

.

[Bob Shaw]

I did have the carbs off for a good cleaning. Readjusted the floats put all back together and the bike ran . I went for a ride and noticed a little hesitation when starting out but it cleared up but continued. I wanted to check the syc on the carbs and it was off. So I started to make adjustments. I did the so well(?????) the bike doesn't run. So I can't make any adjustment until it runs. No I did not do a bench sync. The gauges I'm using are the four vacuum gauges. My manual doesn't show how to do a bench sync so
I am at a loss there.

[Steve]

At least it's easy to remove your carbs.

1. Remove the carbs (you know all the steps necessary, so I won't detail them here)
2. Keep in mind which carb is #3. It's the one with the pulley that the cable attaches to.
3. Hold the carbs up to a light. Look into the engine side, with the light on the airbox side.
4. Adjust the idle speed screw so you barely see a sliver of light under the butterfly of #3.
5. Adjust the 2/3 sync screw so #2 has the same sliver of light.
6. Adjust the 1/2 sync screw so #1 has the same sliver of light.
7. Adjust the 3/4 sync screw so #4 has the same sliver of light.
8. Snap the throttle open and closed a few times, make sure all the slivers are still about the same size.
9. Put the carbs back on the bike.

Before you use your gauges again, fabricate a multi-T setup so you can connect all four gauges to one carb. You need to do that so you can tweak the gauges so they all read the same. Once they are all reading the same, you can remove the multi-T setup and connect the gauges to one cylinder each. That way, you will know that any differences in the readings are due to the engine, not the gauges.

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[Bob Shaw]

Ok, It sound fairly easy. Thanks

[Bob Shaw]

I just want to say Thank You to all of you guys that have helped me with my mechanical endeavors on my GS850G. I did the bench sync and it worked out fine. Thanks once again.