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Carb flooding one cylinder? (fireblade 919)
Benzo - 22/8/11 at 03:03 PM

Hi Guys,

wondering if anyone could shed any light on my carb problem..

I have just built up my engine from a quick strip down and check over a few weeks ago..

I have just remounted my carbs and when the engine is running, i can see down one of the trumpets that it is totally flooding the 4th cylinder with fuel.. (i can see a steady flow of fuel filling up the trumpet in below the slide.)

What would cause this?

Im not too experienced with carbs, but my 1st impression was a sticking float?/float problem?

I didnt want to start and dismantle the carbs because i know they are quite finely tuned piece of kit and i am more of a lump hammer and sledge kind of guy!!

Any help appriciated.

Iain

[Edited on 22/8/11 by Benzo]

whitestu - 22/8/11 at 03:11 PM

You are right, it is likely to be a sticking float valve. They are easy enough to remove and clean out.

Stu

Benzo - 22/8/11 at 03:13 PM

quote:
Originally posted by whitestu
You are right, it is likely to be a sticking float valve. They are easy enough to remove and clean out.

Stu


Great off today so im going to give that a rattle now to see if it solves my problem

norfolkluego - 22/8/11 at 05:29 PM

If you've flooded the cylinder make sure you change the oil, could well be contaminated with petrol

Benzo - 22/8/11 at 05:59 PM

quote:
Originally posted by norfolkluego
If you've flooded the cylinder make sure you change the oil, could well be contaminated with petrol


Very true mate thanks for that..

Now i am having another problem, fitting the carbs with the AB performance airbox is a real PITA..

I am having trouble with the revs now dying fast enough, i have thought maybe the spring on the throttle return could be the problem but cannot find anything wrong..

only other explanation i can find is that maybe it is sucking in some air and the carbs are not tight enough sealed?

That would cause the engine hold onto the rev slightly wouldnt it?

Its just not as sharp as it should be in the revs dying.. the throttle isnt as snappy as it should/has been before..

Any other ideas?

AB Airbox really is meant to be a great job with the jetting kit, but it really is a piece of poo to fit properly.. if you have it on and off regularly you will know what i mean

Peteff - 22/8/11 at 07:21 PM

quote:
Originally posted by norfolkluego
If you've flooded the cylinder make sure you change the oil, could well be contaminated with petrol


If the cylinder was that flooded it would have hydrauliced and bent a rod, I wouldn't worry about it too much. If the carb rubbers are good the only air will be the other side of the intake, it might be ineffective spring or slides sticking.

Benzo - 22/8/11 at 07:35 PM

Thanks guys, up and running again now

Benzo - 23/8/11 at 08:26 AM

Out for a rip last night, all appears fine.. Forgot how much fun it was! Can't wait to get an '08 CBR1000RR engine in!

gixermark - 23/8/11 at 12:10 PM

ha.. have had many frustrating evenings playing with those airboxes seem to work well when on though