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HELP!!! from a bike carb expert!!!
spiderman01980 - 2/6/10 at 09:12 PM

what are theese holes circle in red?
i seem to have petrol flowing out of them!
what is there job what are they there for?

prawnabie - 2/6/10 at 09:18 PM

Look like air correction holes, have you got the fuel pipes plumbed up right?

trikerneil - 2/6/10 at 09:25 PM

Possibly floats stuck or float heights set incorrectly.

Neil

Dingz - 2/6/10 at 10:05 PM

What fuel pump are you using?

trikerneil - 3/6/10 at 05:10 AM

Good point Dingz, those carbs are probably designed to be gravity fed.

Neil

David Jenkins - 3/6/10 at 06:25 AM

If this is the first time you've connected these carbs - I'd suspect that you're putting fuel into the wrong pipes, maybe the ones that vent the top of the float chamber...

...but otherwise - sticky float valves or too high a fuel pressure, as stated above.

Surrey Dave - 3/6/10 at 07:45 AM

Probably floats stuck or too much fuel pressure you only need about 1 - 1.5 lbs on bike carbs, a lot of people use a bike pump which automatically cuts off , or you can use a filter king fuel regulator but it has to be set very low, an accurate way of measuring the pressure is with a clear vertical tube 28" per pound of pressure? can't remember off hand......

tony-devon - 3/6/10 at 07:50 AM

if its all of them that are leaking out, then its a bit unlikely to be the float needles

sounds like excess fuel pressure

them carbs are normally gravity fed

either lower the pressure on the fuel pump

or

I once put a small tank above the carb height, then fed the pump to this with a return from the top to the main tank.

was my simple dodge/cure

NigeEss - 3/6/10 at 08:28 AM

quote:
Originally posted by tony-devon

I once put a small tank above the carb height, then fed the pump to this with a return from the top to the main tank.

was my simple dodge/cure


Sounds like a neat alternative to a swirl pot too

tony-devon - 3/6/10 at 10:14 AM

it was a method that I used on a custom bike

the fuel tank was hidden/integral with the frame, but with a tiny tank in the top tube of the frame to provide the gravity feed for the carbs

the fuel was fed at its own pace, the system worked very well

r1_pete - 3/6/10 at 11:08 AM

1st question as has been asked, where have you connected the fuel, should be into that plastic T, with the pipes feeding 1&2 and 3&4.

The other pipes on show are water heaters and can be discarded, from memory there are two more higher up the carbs which are vents.

spiderman01980 - 3/6/10 at 07:20 PM

a Facet fuel pump which i think it pumps bout 4 to 7 psi! i have been advised to put a regulator on it, but it was doing that when i put a little tank above it with out the pump!

quote:
Originally posted by Dingz
What fuel pump are you using?

spiderman01980 - 3/6/10 at 07:24 PM

yeah its connected to the T!

quote:
Originally posted by r1_pete
1st question as has been asked, where have you connected the fuel, should be into that plastic T, with the pipes feeding 1&2 and 3&4.

The other pipes on show are water heaters and can be discarded, from memory there are two more higher up the carbs which are vents.

David Jenkins - 3/6/10 at 09:25 PM

quote:
Originally posted by spiderman01980
a Facet fuel pump which i think it pumps bout 4 to 7 psi! i have been advised to put a regulator on it, but it was doing that when i put a little tank above it with out the pump!


Far, far too high a pressure - a bike pump gives about 1.5psi but with a high volume. I know that you've tried a gravity feed, but you'll have to sort the pump out regardless of whatever's causing this issue.

FASTdan - 4/6/10 at 07:16 AM

Our facet redtop works well with the ZX9R's using a filterking style regulator to turn the pressure down to 1.5psi.