1979 GS1000 Carb Identification

[jyck]

Hi, everyone. I picked up what I was told was a 1979 GS1000 (not sure which model) but it starting to appear to be a frankenbike. Although the frame and engine VIN match that year the tank doesn't appear to be typical of a 1979 (it indents at the knees).

Also, the airbox didn't seem to fit so snug and wasn't running a filter. I'm not sure if it's the airbox that's not stock or the carbs.

Attached below are pics of the carbs. They read "Mikuni Kogyo" and on the other side "Made in Japan" & "MIC".

The intake inside diameter measured 39.67mm and inside diameter on the other side was 29.58.

Jet size reads 122.5, which from all my research thus far is not stock.

Any help in identifying these would be greatly appreciated.

[jyck]

I should also mention that I can't find anywhere to attach the choke cable which is also suspect of non-stock carbs.....

[Nessism]

Those are aftermarket VM29 "smoothbore" carbs. Cleaned up they sell for $600+ on ebay. Nice score.

[TheCafeKid]

Ed is correct. Clean em, sell em. Use the money to buy yourself a nice stock NOS tank or something. Those carbs are bloody useless to you unless you're planning on hopping that thing up pretty good.

Your tank is off an 80-81 1100E/80-82 750E. Looks pretty ok too, Id sell it as well and buy the bits you need to put your 1000 back to stock. .

[Big T]

That is indeed a frankenbike

It appears to be a 79 E model with

29 mm smoothbores

78 tail piece

80's 750 or 1100 tank

I don't know why anyone would put smoothbores on with a stock exhaust.

You're correct, the jetting is way too big. Stock is 95, maybe go to a 102.5 tops.

They'll fit the airbox better if you get proper sized hose clamps, like on the intake side

[jyck]

holy crap. I wasn't expecting this at all.

You guys seem to know your stuff, so let's entertain the idea of "hopping it up"? What would that entail?

A. Better exhaust?

B. Better ignition. It's got an Accel "super coil" ignition system

C. Better suspension?

[BassCliff]

Greetings and Salutations!!

Hi Mr. jyck,

The standard "hopping up" procedure includes a (Vance and Hines) 4-n-1 exhaust, (K&N) pod filters, and possibly a Stage 3 Dynojet kit or other jet modifications to account for the increased air flow. You might consider a Dynatek electronic ignition upgrade. You'll find suspension upgrade information in your "mega-welcome". But actually I just want to share some GS lovin'.


I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[7981GS]

jyck, that bike looks sharp as it is!
Big T is correct in it being jetted rich.
With a 4-into-1 exhaust and pod air filters, try something closer to 100 for jetting.

Daniel

[tkent02]

If someone paid the big bucks for those carbs, they may have built up the engine too. Possible you might have a real rocket with a bigger bore, higher compression, maybe a lot more. Seems odd to stay with the stock air box and 4-2 pipes in that case, but POs have been known to do some pretty stupid things. Find out what you have in there.

[SqDancerLynn1]

Standard jetting doesn't apply those are 29mm smooth bores, not stock 26mm. With a pipe and pods it may well be close on jetting.. If you look there is a lever on the left side carb!! that is the choke

[7981GS]

With a pipe and pods it may well be close on jetting.. If you look there is a lever on the left side carb!! that is the choke

Like this:



The jetting on my 1085 is 112.5.

Daniel

[jyck]

If someone paid the big bucks for those carbs, they may have built up the engine too. Possible you might have a real rocket with a bigger bore, higher compression, maybe a lot more. Seems odd to stay with the stock air box and 4-2 pipes in that case, but POs have been known to do some pretty stupid things. Find out what you have in there.

What should I be looking for specifically?

Also, it looks like there are two models of Vance & Hines 4 to 1 exhausts. A no baffle drag race and megaphone.

With the 122.5 jet size, would the drag race model be more appropriate?

[tkent02]

What should I be looking for specifically?

Start with a compression check, then look at the cams while you have the valve cover off to do the valve adjustment. Look at the top of the pistons through the spark plug holes.

With the 122.5 jet size, would the drag race model be more appropriate?

Only if you watch too much NASCAR, and no longer have any desire to turn right. The drag pipe drags terribly in the right turns.

[Nessism]

Plus, you don't change your pipe to match your jets, you change the jets to match the pipe (and cams, pistons, etc).

I bought two different GS1000 with unbeknownst to me, built engines. There is a pretty fair chance your engine has a big bore kit and hot rod cams as Tom suggests. A visual inspection will tell the tale regarding the cams, but the pistons are harder to tell. I'd do as Tom suggests and look in though the spark plug hole and try to compare the shape of the piston dome with stock. If you do a search on ebay for "GS1000 pistons" or something to this effect you should be able to find some photos that will help with the ID.

Good luck

[Suzuki_Don]

The drag pipe drags terribly in the right turns.

Tom is that why they are called DRAG pipes???????????????