carbs and fuel problems

[lubricantpixie]

right i was wondering whether anyone knew how to set the fuel mixture because at the moment my bike is running so rich is backfires when i start due to unburnt petrol in the exhaust. also i was checking my carbs and noticed that there is an open t-piece on the longest bridging pipe that connects carbs 1 and 4 does anyone know what this is supposed to do, everyone else i know with a zxr has just got a single connection pipe???

i have had a problem with the fuel pump but now i have replaced it and its working fine, the problem is that it will rev fine stationary all the way to 12000 rpm but when i am riding if i twist the throttle to quickly it burbles as if it has too much air and anything over 8000 revs with the throttle relaxed still burbles. is this just bad carburration??

[RedexRobB]

Got a picture of the pipe mate? Could be that T peice is letting in air and playing with your carburation. Also is it a pipe thats underneath the carbs?

[lubricantpixie]

yeah sorry i havent got a pic, on the tuning bit of the site where the carb balancing bit is, the picture that shows the two pipes under the carbs. its the long one of the two which has the open t piece. when you cover it with your finger the bike revs a little higher.
this shoudln't be the problem though as it has been like this since i have had the bike about a year and a half and this is the first time my fuel mixture has been playing up.

any ideas on setting the mixture as well?

[RedexRobB]

Well for a start that pipe shouldnt be like that, that T piece is probably from a scottoiler kit (for the vaccuum to operate the scottoiler reservoir) and someone hasnt replaced the pipe once they removed the kit because it needs to be sealed. You could use a screw with a bit of silicone sealer on it, screw it in and with any luck will seal it, otherwise you'll need another pipe.

Not sure what the next step is, id seal that T peice up and see how it goes from there mate.

[lubricantpixie]

yeah ok i will do that to see what difference it makes but i still need to fix my fuel air mix. cheers for the help though rob

[rover220]

that pipe wont be helping as it menas you will have unmetered air entering the engine, this WILL mess with fuelling

[RedexRobB]

no probalem pixie, exactly as Rover said really, i expect the bike will run alot smoother and will instantly sort your bike!

[beatrootboy]

Pixie gaffer tape the end of the pipe, go for a ride round the block if it sorts it your in,i had a similar problem with the burbleing up to 3500 revs and if i gased it hard at any revs it burbeld and id have to pull off and back on slowly to get going,turned out it was the race pipe i had on, the last owner fitted a full micron race system,but didnt adjust the fueling,put a road legal pipe on,and it fixed it right up,check your throttle cables as well, might be sticky good luck!

[lubricantpixie]

nice one its good to know someone else has experienced a similar thing. i am going to replace the pipe, balance the carbs and hope its better if not i will undoubtebly be asking for help again.