Z900 A4 fuel leak any ideas please?

[Mally]

These may help?

[Mally]

Fully rebuilt for your info to reference tee pieces, float level check tool in place.

[Mally]

Keyster kits for Kawasaki are good, have heard of problems with kits for 2 stroke Yamaha’s.

That's putting it mildly , but your right, caused me no end of problems on my RD 250 rebuild.

Got genuine in my Zed and now in my RD .

[Gray17]

Wow your carbs look like brand new, did you have them vapour blasted or ultrasonically cleaned or both? Wish mine looked as good, that said they at least have all new internal conponents so hoping theres a vast improvement in running.
Nigel and everyone else has been very helpful and whilst i have no doubt Genuine Mikuni parts are ideal, think the Keyster are a very close 2nd least for Kawasakis, think from comments Yamaha ones better original.
Perhaps if it had just been jets i would have gone down that route but all the internal components were cheap copies and not suited to the bike so had no choice but to replace them all.
One thing i did notice on your photos the T pieces seem to enter all the way in, both o rings, mine by comparison only the 1st enters the 2nd o ring is on the edge, however they dont seem to leak at all.
What i cant understand is my T pieces are brass, the o rings are set in the grooves and once carbs are fitted to the bracket cant move, so either thats the way they've been made or somethings shrunk which isnt possible, unless their the wrong T pieces for the carbs?

[zed1015]

What i cant understand is my T pieces are brass, the o rings are set in the grooves and once carbs are fitted to the bracket cant move, so either thats the way they've been made or somethings shrunk which isnt possible, unless their the wrong T pieces for the carbs?

If they are brass they are non stock aftermarket or home made.
The originals were only ever aluminium with either the bonded rubber sleeves or 'o' rings but if your brass ones don't leak it isn't really a problem.

[Gray17]

Thanks for reply, well the T pieces look brass to me, but then i thought the plungers i sent you were alluminium but wernt so what do i know.
On the plus side rebuilt and fitted carbs to bike, started up straight away but was still running rough, all 4 seem to have same ouput from each exhaust but 3 of the cylinders front pipes were very hot but one wasnt. Turns out the plug was faulty. Decided to replace all 4 as no idea how old and had beenvery sooty, Tried to get some new NGKs rang every bike place in Hull, Euro car parts and Halfords all said same thing we only do the resistor type now none resistor are special order 5 days. Luckily had 1 spare so fitted that bike ran a lot better but still wouldnt tick over at less then 1500. When you open throttle it bogs down bit if you open a bit more it revs freely. I took it out for a run. When you 1st let out the clutch the revs die even if you open the throttle so you have to slip it a bit, but once moving it picks up good, mid to top revs are good too with no hesitation and pulls well only took it to 5k. Did a 30 mile round trip, no leaks choke a lot better Thanks Rob and Carb kits have made vast difference. I just need to get the slow to mid sorted now. Nigel has given me some tips to check he thinks its got an air leak somewhere which could well be the case. Just need to find it now. When i returned from run i removed all 4 ugs they were all chocolate brown, which is ideal, so on main jet at least its as it should be, just need slow running sorting.
At least ive got a runner and everything works, front brake needs a massive pull to get working seem to remember that from my younger days maybe need some better pads?
Bike handles ok but its a bit lethargic in corners to say the least.

Maybe just need to get used to the 40 year old chassis!
Many thanks to all who helped get me mobile, im very grateful.
Maybe it just needs a good tune up now to get it spot on. Or perhaps I do!!! Ha

Heres some photos of finished article.

[gray]

Maybe the needle positions needs moved a notch ( carbs out job tho' - sorry) - do a plug chop at 1/4 -1/2 throttle open to see what the midrange mixture is looking like.
Easy to tell if you have an air leak - some Easystart or other flammable spray eg carb cleaner , sprayed around the back of the engine, 1 area at a time with a fine nozzle - if the revs rise you've found it - but that would usually not affect all 4 carbs equally

[gray]

Tyre pressures make a surprising difference to how the handling feels- Back in the day I used 32 front and 36 back with the tyres of the time, but modern tyres seem to need 34-36 front and 40-42 rear - if your using worn but "modern" tyres, and the pressures you used to use in the 1980s, that could explain it

[Gray17]

Thats a very good point about tyre pressures they are modern tyres will try increasing pressure as you suggest, to me it felt like it was almost going to fall over in the corners and i wasnt going that fast, that said i re built a Suzuki GT750 had 1 in the 70s and it handled terrible, wallowed and wasnt stable back then TT100 front and Avon Speedmaster rears were the tyres of favour, when i rebuilt i fitted Avon Roadriders, it handled superbly for a 40 year old bike. The Kawasaki has had the needle roller swing arm mod and new front steering bearings as well as tyres so hopefully that will improve withextra PSI, as for checking carbs for air leak thats exactly what Nigel suggested, will have to get some easy start. As for checking plugs at 1/4 and 1/2 throttle thats not so easy as it takes a while to assess. I did remove them after starting it and ran it for several mins till it ran off choke then checked they they were black and sooty but guessed that was as it was a rich mixture for starting.
As i say it wont tick over at 1000 revs it needs 1500 but not sure tacho is correct as it sticks, got a new one to fit.
Thanks

[Bill P]

Bike looks great well done

[Mally]

Bike is looking great , very nice job .

As been said potential air leak and use the spray to identify leak . If it doesn’t identify anything then investigate your pilot circuit for issues.

Be wary of where you get your plugs , loads of fakes out there , you can get them from ZPower if you can’t source locally.

My carbs were vapour blasted and then I ultrasonically cleaned them and all the components ( I have my own ultrasonic cleaner) , then rebuilt with as many genuine parts I could get ( need to get those Viton choke plungers from Zed 1015 , got them on my RD). Dare I say with Mikuni jets.

I think the tee pieces you have were aftermarket ones ,seem to remember them for sale somewhere years ago , but as said if they aren’t leaking then they are ok .

You didn’t say ( or maybe you have in previous posts ) that you have balanced the carbs but seems to be running reasonably at higher revs but would smooth things out .

Good luck , sounds like you are nearly there .

[Ultim8pc]

The brass tees are aftermarket and they are superior to the OEM ones in terms of performance and longevity. These outsell the OEM one by 10-1 and are a good alternative if you want reliability and don't care that it's not original.
They should push in all the way so both o-rings are inside the body.

I spoke with Grey at length on the phone yesterday and went over his issues and he has a list of things to look into.
If he doesn't get sorted I may be able to call in for a visit as I am over his way to see relatives every now and then.

[Gray17]

Thanks for all the replies and advice, as has been suggested the only way to resolve it is to eliminate each part in turn.
I was hoping the new carb kits and choke plungers would be a miraculous cure, and the bike does run 100% better now ticks over steadily be it at 1500 and revs well. Also no carb leaks showing new float valves working well.
So armed with the advice i have ordered a set of 4 Denso plugs, a Xenon timing light so i can confirm timing and advance mechanism. and set of 4 vac guages, as pointed out once used can always be sold on. Ive also got a can of easystart.
Next step tank off yet again and cam cover off to re check valve timing just in case. Once ive checked this its air leaks from various points to check.
Keep you all posted

[marmck]

Just check all 4 vac gauges read the same . I bought some & couldnt get them the same so tried 1 gauge on each carb at a time to set them in the end . Glad to here your just about sorted . Regarding setting off i always blip the throttle a bit then release clutch & open throttle .

[warren3200gt]

"set of four vac guages", which ones Graham?
There are some real cheap absolute rubbish chinese guages available on various auction and dealer sites. The only way to tell if the ones that turn up are reliable is to test each of the four guages on the same cylinder in turn. Obviously they should all read the same for that cylinder but if they don't then all you'll be doing is adjusting in a vac discrepancy not adjusting it out.
Even the carb tune Pro is unlikely to read the same on each bar for the Same carb but at least you can easily adjust them so that do.