98 ZX9 CARB ISSUES

[Leigh]

Hey guys,
Sorry it's been so long since I've stuck my head in. Bloody bike has been giving me nothing but grief.

The short version is this :
It idles ok but when I take off it is fluffy up to about 2500-3000rpm. Then it brings the A-game.
All at once. Leant over in a wet roundabout when it all cuts loose is no fun. No, really, it's not.

So, I've torn the thing apart looking for dramas.
There's a bit of needle wear, but no more than you'd expect.
I checked the diaphragms, as was suggested by Kwak addict. All good.

Everything looks fine.
Many cans and much head scratching in the shed leads me to check the main jet size.
Maybe it's go a kit in it, methinks.

150 main jets. What?
They should be 155.
So, previously, some cheap bastard has gone down in jet size to compensate for a bit of needle wear.
Now with the Yoshi & BMC it's running like a 3 legged dog.

I rang Kawasaki. They only have one 155 jet in Australia.
eBay has nothing.
Dynojet or Factory Pro are a 6 week wait.


So, calling upon the brains trust, does anyone know where I can get a set of 155 main jets?

[MadKaw]

I bought mine from Show and Go in S.A.

http://www.showandgo.com.au/

I had a full a akro, ignition advancer, bmc race some head work and ran 158 mains..

[Leigh]

Aah, thanks. I had a look at their site and nearly drowned in numbers.

As far as I can tell the bike is stock apart from the Yoshi/BMC combo.

[oldmanmike]

Clive Carter has jet drills, good 2 stroke warrior that he is. He should be able to take your 150's up in size.
BTW float levels critical to your problem also ??

[Leigh]

Thanks Mike.
I wondered about drilling them out.
Dynojet say no but of course they would, wouldn't they?

Show and Go have come through for me.
New jets are on the way..

I reckon I'll keep the 150s aside and run them out to 157 or 158 just to see what happens down the track..

[Slow and wobbly]

Not sure if it helps.
I had the 2000 and I am unsure whether the setup is the same. As in if the needle has a clip or not.
On a standard Jetting, filter and exhaust the bike behaved like a cantankerous bitch around that rev range - has to do with ADRS. After changing the muffler to a slip on Muzzy and a K+N filter all that was required was to raise the needle by adding a 1mm washer - no jetting required and it improved remarkably. While your ordering stuff from Show and go get them to throw in some washers also - I think they charge .80c each for them. May help with your fettling. If your needles have a clips and notches to raise and lower then drop the clips a notch before changing jetting and note whether this makes a difference.

[Kwak addict]

If the bike has sat for any length of time, the pilot circuits will be blocked, very common nowdays with shit quality fuel evaporating & clogging up the tiny orifii.
Take it to Dynobike & they'll charge you $900 to fix it Or do what I did & sort it yourself in a couple of hours.