GS1000 Carb problem.

[Froudster]

I'm posting this for a friend so I've just copied and pasted it from his post in another forum if anyone can help please.

I have a gs1000 with slide carbs and they wont create a vacuum to open the fuel tap
can anybody shed some light on this problem

Temporarily I have blanked all 3 carb pipes and removed one of the allen bolts on the head ( carb balancing port )
then fitted a brass connector so i can use a pipe from my carb balancing kit and now the fuel tap works


there must be a problem inside the carbs has anybody else had this problem?

[tkent02]

The vacuum hose should come off the nipple on the #3 carb, the other carbs just have vents.

[Froudster]

Right then, here's where he's at so far.

ok the third carb that sounds good to me as ive got my crappy old carbs still with the pipe attached to the third carb thats 1 being under the tap 2 next to it and the third being next to that and forth is on the right as sitting on the bike

but anyway arnt they all connected inbetween have a look at a set and you will see why im saying that

i also assume each carb will provide a vacume on each stroke ,so four strokes makes a constant ish pulse of vacume and i assume they are all connected to eachother via the carb passages thus making the constant single outlet to the tap

also may i point out if the above is correct that it shoudnt matter what pipe i fit it to

so from my own deduction there must be a leak inbetween the carbs possibly on the connecting passage rubber pipes


I MAY BE WRONG ITS JUST LOJIK ME FINKS

my tempory fix (please read top posting for details) just to get the bike running will not surfice as a perminent fix
as the fuel flows and stops pulsing because im only getting vacume from one cylinder and this also makes me think they should all be connected inside

[TheCafeKid]

Actually, it MUST be on the number 3 carb. The bodies, while they may look identical, are NOT. if you were to switch them around, you'd be in a bit of trouble. 3 has a block off in the float bowl that creates said vaccum. Putting the tube on any other carb wont suffice. I say this, but i dont exactly know what you have done, as I couldnt quite follow it clearly...

[Froudster]

Thanks CafeKid. Will post more details as I get them from him

[renobruce]

#3 goes to the petcock. The other ports on either side of #3 are vents. If the bike is stock, run some tubing from those to behind the airbox. If the bike has an aftermarket pipe and/or pod filters, leave the hoses off those ports. DO NOT hook them together.

That is the only set-up that will work.