78 GS1000 carb refitting

[Guest]

Hello All.

Had my carbs apart for a good clean etc, did the shims too, but trying to get the carbs back onto the rubbers is driving me nuts, they seem to just not want to go on, should I be trying to push them into the carb rubbers on the cylinder head first, or into the air filter rubbers first .. ?

I remember my 1980 GS1000 with the CV carbs would take 2 mins to get back on, what am I doing wrong?

Thanks Guys.. Any help/advice would be appreciated.

[Rijko]

Yep, the CV carbs are way easier.
Your carbs go into the cylinder boots first.

first, take out the 2 bolts on top of the air filter box.
This gives your some extra wiggling room.

Next, find something that makes rubber slide more easily.
Pun intended
WD-40, silicone spray, dish washing soap ...
Apply a very small amount to the insides of both
cylinder boots and airbox boots. Just enough to make
them slippery.

If you have a small plate that is a bit larger than the carbs,
that's helpful but you can do without it.
Helps the carbs slide easier into position.

Next, put the carbs in the cylinder boots, keeping the airbox
side of the carbs above the airbox rubbers.

airbox trick 1.jpg

[Rijko]

Now wiggle the back of the carbs down slowly and it should
all slide into place.

See pics, the metal plate is helpful but not necessary.

Make sure all 4 airbox rubbers are seated properly on the
carbs, especially with older boots this can take some fiddling.

airbox trick 2.jpg

[Tom R]

And consider buying new ones that haven't gone through a million heat cycles and are actually still pliable. They'll seal up better too - if you're having any vacuum symptoms, those old carb holders are a good place to start looking.

[tatu]

WD40 is bad for rubbers and plastics, if lube is required then silicone grease or Vaseline, I think KY in American.
I found that lining the carbs into the stubs at an angle from underneath and rolling them upwards does the job very well. the air box needs to be unbolted.

[Rijko]

And consider buying new ones that haven't gone through a million heat cycles and are actually still pliable. They'll seal up better too - if you're having any vacuum symptoms, those old carb holders are a good place to start looking.

good one... and if you're not replacing the boots, at least replace the o-rings between cylinder head and boots if you haven't done so already.
Those are notorious for creating issues by sucking in false air.

[GS1000OZ]

Thanks Guys,

I had another go and got them in, bike started after a while once some fuel got into the carbs and ran really sweetly with no spittinspluttering/backfiring, I reckon the exhaust shim on one cylinder was waytoo tight and causing the drama.. so I'm glad I did the shims..., Anyhow..then fuel leaked from the inlet T piece between the carbs, looks like rubbers/o rings are knackered ( Yep, I should have changed them.. ) Any suggestions where to get them from? I'll change the fuel hose too whilst they are off again, it's gone a bit rock hard.. Anything else I should do once I have them back on the bench that may save another removal/headache.. :-)

Thanks
Mick

[Rijko]

good the bike runs nicely.

Anything else I should do once I have them back on the bench that may save another removal/headache.. :-)

The o-rings on the intake boots should be replaced, they are known to fail.

http://www.cycleorings.com/intake.html

O-rings inside the carb i replace, too.

http://www.cycleorings.com/VMkit.html

check if this has any tips for you :

http://gsarchive.bwringer.com/bikecliff/images/vm_carb_rebuild.pdf

Personally i would replace the float needle and seat, they start leaking so often i don't wait for them to fail anymore. I resent the puddles on the floor.

Fuel tee : those rubbers are not for sale by Suzuki, nor is the tee anymore.
i have fitted one of these, works great :

http://www.ebay.com/itm/Suzuki-Carb-Fuel-Tee-Nipple-Alum-GS1000-GS1100-GS1150-039-80-039-86-/281996211709

s-l1600.jpg

You could also fit a fuel filter, the gas tanks often are dirty or rusted and Murphy's law usually ensures that finds it's way into recently cleaned carbs

[Big T]

Thanks Guys,

I had another go and got them in, bike started after a while once some fuel got into the carbs and ran really sweetly with no spittinspluttering/backfiring, I reckon the exhaust shim on one cylinder was waytoo tight and causing the drama.. so I'm glad I did the shims..., Anyhow..then fuel leaked from the inlet T piece between the carbs, looks like rubbers/o rings are knackered ( Yep, I should have changed them.. ) Any suggestions where to get them from? I'll change the fuel hose too whilst they are off again, it's gone a bit rock hard.. Anything else I should do once I have them back on the bench that may save another removal/headache.. :-)

Thanks
Mick

The 78 carbs typically don't have O rings on the fuel T. Just leave it overnight to swell up and the leak will probably stop.

Fuel lines, carb boots and other "rubber" bits are old and you should consider replacing these 39 year old parts.

I can take my carbs off and on in 15-20 minutes.