1979 GS850GN carburetor options

[rvitarella]

I recently acquired a 1979 GS850G, unfortunately it has been sitting since 1992 as far as I can tell determined by the last year on the license plate. I got to cleaning the carbs, and carb 2 is not in usable condition, the pillar that the main jet screws into is corroded away, and isn't going to seal properly. Would a GS750, or a GS1000 carburetor from the same year in the same position fit if I changed out all of the jets, and brackets?

[Big T]

Yes, the VM 26 carbs are; interchangable, as you mention, all of the brass from your ruined carb must be swapped over

[Nessism]

There are differences in the pressed-in air jets, but I don't know if you will notice when running.

What position 850 carb do you need? I have a few spares.

[rvitarella]

It is position 2. I took the chance before I got the reply and bought a set of 79 gs1000 carbs.
The manual I have says:

45100

Main Jet Paint Suggestions!!!!
Needle Jet 0-4
Jet Needle 5DL36-2
Cut Away 1.5
Pilot Jet #15
Air Screw: PRE-SET
Pilot Screw: PRE-SET

I read through the carb oem specs post, and saw the below post, which is weird to see the 82 with the vm26, but maybe it was just in the same manual. Which one is the Air Screw, and which one is the Pilot screw. I wish they would have given some setting to go by if they get screwed up.

1982 GS850G
----------------
Carb. type: Mikuni VM26SS
Bore size: 26 (1)
I.D. no. 45100
Idle rpm/min 950-1150 rpm
Fuel Level 3-5 (0.12 - 0.2)
Float height 23-25 (0.91-0.98)
Main Jet Paint Suggestions!!!!
Main air jet ??? if this is the cutaway, it is 1.5
Jet needle 5DL36-2
Needle jet 0-4
Pilot jet #15
By pass 0.8
Pilot outlet 0.6
Valve seat ???
Starter jet #32.5
Pilot screw pre-set
Pilot air jet 1.2
Throttle cable play ??
Choke cable play ??

[Nessism]

Rebuild tutorial here... https://gsarchive.bwringer.com/bikec...rb_rebuild.pdf

You should do a full teardown, and replace all he O-rings. I have O-ring kits if you are in need. Gaskets are available at lots of sources.

Also, remove the carb boots, flex them, and look for cracks, and replace the large O-ring against the head.