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Old 12-09-2014, 01:46 PM   #1
Reista OP
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Carb Questions

Just bought this gem out of a shed for $200. There's cosmetic rust and the tank needs work, but all this bike REALLY needs to run is... The missing carbs. (oh yeah, there are only 5,600 miles on it XD)
Carbs for the 80-81 GS750 are insanely hard to find so I'm looking at either putting GS850 carbs on it or trying to stuff the VM carbs on the engine.

The specs are all VERY close to one another apart from the starter jet. I'm also probably going to put pods on so it might compensate a bit for some extra fuel. Stock exhaust would be kept.

a GS850 carb on the GS750 would change the following specs:

Jet changed - 750/850

Main jet - 112.5/115
Jet needle - 5C28/5D50
Needle jet - Y-4/X-5
Pilot Jet - #42.5/#40
Starter Jet - #50/#32.5

Everything else is the same, both models use the Mikuni BS32SS


Reista screwed with this post 12-09-2014 at 01:54 PM
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Old 12-09-2014, 01:57 PM   #2
KirkN
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So, um..., what was yer question?

But, for best advice on all things GS, head on over to the forums at http://www.thegsresources.com/
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Old 12-09-2014, 02:04 PM   #3
Reista OP
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Quote:
Originally Posted by KirkN View Post
So, um..., what was yer question?

But, for best advice on all things GS, head on over to the forums at http://www.thegsresources.com/
I like the GS Resources, but their forum is... kinda ghost-towny

My question is - Is it nuts to put 850 carbs with pod filters on a 750?
All the other info is just technical stuff laying out the differences in the jets
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Old 12-09-2014, 02:31 PM   #4
Tim_Tom
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As a former GS850 owner, throw on the 750 carbs, post cleaning of course.

Then size jets and tune carbs according to the manual and your modifications. At least with the pods they will be real easy to remove when you need to shim the needle or fiddle endlessly until is set up properly...

Good luck keep us posted! Can't go wrong with a good running GS!

Tim_Tom screwed with this post 12-09-2014 at 04:40 PM
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Old 12-09-2014, 04:06 PM   #5
Reista OP
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Picked up some GS700E 1986 carbs for $120 in good condition (same model, different jets)

The main jet is much larger (you can see it on the graph on original post) and it came with super dirty K&N long pod filters which would have been $60-80 anyways so I didn't see any harm in it. Even if I have to rejet the carbs to spec, $120 for the mikuni bodies isn't bad. Not too sure how I feel about the black plastic tops that were put on the carbs on the GS700 model though XD easy enough to change though.

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Old 12-09-2014, 04:39 PM   #6
Tim_Tom
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Those tops shouldn't be plastic... looks like someone painted them with truck bed liner to me. It ought to be removable.
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Old 12-09-2014, 04:53 PM   #7
Reista OP
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Quote:
Originally Posted by Tim_Tom View Post
Those tops shouldn't be plastic... looks like someone painted them with truck bed liner to me. It ought to be removable.
Actually on the factory 1982 GS700E they are plastic. It's the only model with plastic tops.

Look veeeeery closely. If the top was the regular aluminum, there wouldn't be a nice clean black line.


The replacement caps on those years of carbs are plastic
AND there are several used plastic tops for sale, or new old stock.

Le proof:

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Old 12-09-2014, 05:06 PM   #8
Tim_Tom
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Well I'll be damned. Learned something new today. I would assume that caps from an older model carb would fit? Then again I also assumed they weren't plastic.
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