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leeking bike carbs
FOZ500 - 28/7/08 at 05:19 PM

Hi all took my beast for a rolling road tune today. But my Bike Carbs seem to be leaking from the two little brass holes in the mouth of the carb and flooding it so much that it is dripping all the time when the fuel pump is switched on with engine running as well as not running so if i turn my fuel pressure regulator down to stop the dripping. It starves the engine of fuel? I check my pressure and it was at 1 1/2 bar. Can it be grit in one of the jets?

mistergrumpy - 28/7/08 at 05:29 PM

Sounds like what I just had. Fuel was dribbling in for no reason. A good cleanout sorted it great.

big_wasa - 28/7/08 at 05:47 PM

21 psi is way to much for bike carbs it should be nearer 4 psi.

[Edited on 28/7/08 by big_wasa]

whitestu - 28/7/08 at 05:47 PM

Has it always been like that?

My ZX6Rs did it as the carbs are mounted at a different angle to the bike. I lowered the float height a bit which seemed to sort it out.

Stu

David Jenkins - 28/7/08 at 06:28 PM

quote:
Originally posted by big_wasa
21 psi is way to much for bike carbs it should be nearer 4 psi.


Absolutely correct - 0.1 - 0.2 bar is typical (anywhere between 1.5 and 2.5 psi, perhaps a tiny bit more).

This is the advantage of using a bike pump - low pressure with high volume, without a fuel regulator.


[Edited on 28/7/08 by David Jenkins]

coozer - 28/7/08 at 07:11 PM

Have you blocked the breathers that would have gone to the airbox on the bike? I did and it caused mine to flood like that.

FOZ500 - 29/7/08 at 04:44 PM

Thanks for all the replies
It does seem to be the angle of the carbs that is the cause of the problem.
I twisted them up a small amount and so far no problems but now I got another problem can anybody tell me where I can get one of them 90 deg Speedo cable ends from? As my speed just stopped working again.