Kawasaki Sportsbike Riders Club - Australia - Online Forum

On the $1000 XJ900 I just bought, when I start it and leave it idle and then turn it off without riding it There are 4 tubes coming from the carbies which drip a little fuel over a period of time.

My question is, is this normal? I have never seen anything like this before but only just got the bike so don't know if it should be happening. Another weird thing is that where the tubes drip they drip right onto the exhaust in an indirect way (hows that for confusing?). I cannot see anywhere that the tubes could be put without them hanging out near the rear brake and gear levers.

Any suggestions or advise would be great.

If it has Mikuni carbs like my GNs- there is a tube which can be seen at the bottom of the carby bowl- it hooks up to a tube in the bowl that makes sure the carbs don't flood above a certain level- it's a safety thing- it shouldn't flow fuel ordinarily- either your float level is too high, needles and seat are leaking or maybe if you have a vacuum fuel tap, it could be faulty coz fuel isn't supposed to flow with these without the engine running unless the tap is set to 'prime.'

I bet it is stuck on "prime"

Can't remember mine doing that on any kind of regular basis...

Its just trying to put itself out of its misery ala the Aprillia cube.

Set fire to it.

I'll bet that my reserve switch is not the original because I cannot get it to the reserve position so if indeed there is a prime setting which way should the switch be. At the moment it is in the up-down position...so according to the writing on the switch its either on reserve or on. the only other option is off but when I switch it there the bugger doesn't die at all so I am guessing that off is not exactly off.

bonester wrote:If it has Mikuni carbs like my GNs- there is a tube which can be seen at the bottom of the carby bowl- it hooks up to a tube in the bowl that makes sure the carbs don't flood above a certain level- it's a safety thing- it shouldn't flow fuel ordinarily- either your float level is too high, needles and seat are leaking or maybe if you have a vacuum fuel tap, it could be faulty coz fuel isn't supposed to flow with these without the engine running unless the tap is set to 'prime.'

I am pretty sure they are the Mikuni Carbs on mine. Also I noticed that its only 2 of the carbs which leak. Can the float levels be different in each of the carbs? So the 2 which leak may be too high but the others might be ok? The bike still seems to go like a train but then I am comparing a 250 to a 900. Would having a high float level in 2 of the carbs cause starting the be difficult at times?

Nah i doubt its the float levels.More than likely its the inlet needles not seating properly.These are either worn or there is shit stuck under them.
The old kwaka thous used to do this type of shit all the time.
Take the carbs off,clean them out and with the carbs upside down with the bowls off,blow into the fuel inlet hose.This will tell you if they are seating ok.Also a good idea to stick an inline fuel filter on the inlet hose before reinstalling.

I actually think the fuel switch is a bit confusing on those things..from memory...the internals of the valve could be shagged...

rocketrod wrote:Nah i doubt its the float levels.More than likely its the inlet needles not seating properly.These are either worn or there is shit stuck under them.
The old kwaka thous used to do this type of shit all the time.
Take the carbs off,clean them out and with the carbs upside down with the bowls off,blow into the fuel inlet hose.This will tell you if they are seating ok.Also a good idea to stick an inline fuel filter on the inlet hose before reinstalling.

all good advice - 'Inlet needles' - do you mean the needle and seat ? These are probably shagged out and need replacing, do all 4 of them, not just the 2 carbs that are leaking out of the overflow tubes. The seats in these carbies have a small wire gauze that often gets clogged up with old fuel residue etc....The fuel tap is a vacumn jobbie, I can almost *guarantee* that the diaphragm inside the tap is brittle and rooted, and that is why the tap has no 'Off' position. (Reserve, On and Prime only)....if you can get the tap off and have it identified properly, its an easy job to replace the diaphragm and also all the o-rings inside the tap. If its a non-standard tap, I would track down a standard fuel tap and fix it up, not spend money on a non-standard part.

You should try and route the 4 overflow tubes together (cable tie), and they should exit in the gap between the swingarm and the rear of the cases, not aimed over the 'zorst pipe

Get these things sorted before you start looking at float levels...

looks like Sunday will be a tank off day. Also, what sorta $$$ in parts would I be looking at to do the carbs and fuel tap? Just gotta prepare the wife.

So you coming round to get the manual then? I am pretty sure it covers all that stuff...I've also got plenty of space in the shed if you need a hand, etc...

Yup, won't be until Sunday though. I'll send you a message before I come.

for the age of the bike, the carbies are an unknown. its worth the sanity check of replacing the following

carb float needles (who knows HOW worn they are, well, without an inspection), emulsion tube (usually brass and has had the shit belted out of it by the steel needle), any and all fuel tubing from the tank to the carbs.

Oh and from the sounds of it, it'll be worth your while draining the tank and checking the insides of the fuel switch. hell when i bought an old bike once, the numbnuts that had it before me put it together wrongly and everything was missaligned.