Cbr 600 Carbs

[richard mackay]

Anybody out there familiar with Cbr 600 carbs that can tell me why I have

fuel pouring out of hoses from tee pieces at top of carbs.

Cheers

Richard

[cb750]

If they are like the fireblade carbs the tees are normally the vents for the float bowls so it looks like 1 or more of your float needle valves are stuck open and overfilling the bowls. Possible causes: faulty needle valve, float u/s, electric pump if fitted at too high a pressure (regulator too high or faulty).

[richard mackay]

Could be the pump. I know that bike carbs only need 2.5 psi my electric pump is an

of the shelf pump I had fuelling a 2ltr pinto. It may be a bit to high eh

Richard

[maccavvy]

sounds lie too much pressure. I have a sytek regulator on my cbr900 carbs running at 2psi

[richard mackay]

May have narrowed it down a bit. I took the tee piece of to leave the two pipes and switch on the ignition.

The fuel came out of the pipe between the carbs that feed the numbers 3&4. Number 4 carb was full of

fuel sitting against the butterfly so could that carb be the problem?

 

Richard

[cb750]

Yes! You need to be carefull if you have fuel against the butterfly as it has probably worked its way down into the cylinder so you have neat fuel sitting on top of the piston and that could be working its way down into the oil. I wouldn't try starting it if I were you until you can check if everything is ok and fixed the overfilling problem. Have you checked what fuel pressure you are getting to the carbs, it may be that there is nothing wrong with the float valve just that it can't hold back the pressure that it wasn't designed for and that carb is acting as a pressure relief valve.

[richard mackay]

Going to order a regulator the same as what Maccavvy has and see if that cures the problem.

Can't do nothing till next weekend as I work away from home. I'll let you guys know how it goes

though

 

Richard

[Snapperpaul]

My CBR900 carbs did this on first start up

Settled down after a couple of starts now ok

Probably the float valves a bit sticky

[Guest 2b cruising]

+1

[richard mackay]

Fitted regulator and it seems to have cured the problem

Richard