KZ900 Carb Re-Jet and Tuning

Can someone take a look at the plugs I posted above? Three of them are completely black. The chart shows that as "Oil fouled" and it has me worried that I have oil where I am not supposed to. They are not wet so maybe I am overreacting? I was expecting them to come out white because of the backfiring on deceleration but they are all black. Does that mean it is running extremely rich or something worse? If you look at the slides they are in a pretty closed position.

Thanks,

Also to note regarding the plugs. I have a Green Dyna ignition pack and accel yellow wires. I am planning on getting new plugs today to see if the rich condition is happening now or if that was there from before.

I am trying to take the carbs off the bike to adjust the slide and check the needle jet position but having a hard time getting them off.
I am following the manual but it doesn't say I have to loose the clamps on the carb holders. Trying but it is secured with an odd sized hex.

Also I removed the top of one carb and there are two bolts in there preventing me from getting the slide out. 8mm socket is too big, 7mm is too small. Any ideas?

pics?

You need to loosen the carb holders to take them off, try soaking the seized hex with a penetrating oil.

Carbs are off and mostly disassembled. Running into an issue with getting the removing the two screws down in the slide, holding the needle in. Two screws are already mostly stripped and I am not having luck with any others. Could these be the JIS screws that people are talking about? No luck with P2 head screwdrivers. Soaking in PB blaster now.

Hi Conspiracy,
Pretty much every screw on any Japanese motorcycle will be JIS. Trying to use SAE Phillips screwdrivers will usually damage JIS screw heads, often to the point of no return.

Once the slides are out of the bore, heating the slide to about 250 F. will ease removal of the screws that attach the plate to the slide.

Good Ridin'
slmjim & Z1BEBE

Hello Conspiracy

can you take some pictures of the two screws down in the slide?

Scirocco wrote: Hello Conspiracy

can you take some pictures of the two screws down in the slide?

Got the screws out on 1 of 4 slides. The other three are damaged. Sitting in PB blaster some more. I ran the heat fun against them for a while, with unintended results lol.

Someone near has two sets of z1 carbs on Craigslist. I am hoping I can get them for cheap. Cannot find any slides for sale online. Anyone know the part number?

Have you tried jetsRus?
Steve
jetsrus.com/

Thank you. I found the slides but having a time finding correct one and correct needle. I should have an order soon though. Thanks agaian

Send him a e-mail. He will get back to you and be sure you get what you need.
Steve

Conspiracy wrote: Cannot find any slides for sale online. Anyone know the part number?

Hi Conspiracy,
Late Z-1A and all Z-1B SLIDE PN# 16025-075 (1.5 cutaway)
All Z-1 and early Z-1A SLIDE PN# 16025-051 (2.5 cutaway)
JET NEEDLE 5J9 PN# 16009-055

Don't mix cutaways on the same rack or idle will suffer.
Unwise to put a set of different cutaways on carbs that aren't jetted for them, or off-idle transition will suffer.

Good Ridin'
slmjim & Z1BEBE