TOPIC:

Hey guys this site has been a world of help, from wire diagrams to carb settings, but I still have some questions... 3 of my 4 carbs are running lean according to my plugs... the fourth one is super rich (wet plug)... how far can I adjust the air inlet screw before I hurt something? The previous owner put plugs in that were a step hotter (I think) and the bike runs decent once it warms up and I enjoy riding it... don't want to hurt it

Clear tube test?
Steve

Have not tried that yet, do I put tube in where the big brass screw is? I've seen pics about how to do but want to be sure

If you have a drain nipple on the bottom, that screw opens the bowl to drain, use the nipple. If not get a fitting that screws into it or use a clear tube that you can screw into the hole. You'll be surprised how far off they are.
Steve

Hate to sound like a noob, but.... how do you adjust the floats? Just bend the metal piece that attaches to the fuel shut off?

Do you have a manual, you'll need one.
Steve

swest wrote: Do you have a manual, you'll need one.
Steve

+1 !!! Ed

Unfortunately no I do not, I'll look online later when I get off of work

Be sure to get a Kawasaki Service Manual for your bike's EXACT year and model. There are big differences between the different year KZ650 models, so if you get the wrong year manual it will not have all the information you need for your bike. You usually can find the manuals on eBay. Ed

Which cylinder is running rich - cylinder #2?

Exactly which spark plugs are in the engine?

Ed

How did you know? Lol. ... I believe it is number 2 it has ngk plugs in it now, I'll get number when I get home

I'm not psychic. It is not uncommon for 1978 and later KZ650 models to have cylinder #2 run too rich. The problem usually is not with the carb; it most often is a problem with the petcock. The 1978 KZ650 came with a vacuum operated petcock. It has a vacuum line that runs from the petcock to the #2 carb. Vacuum running through that line operates a diaphragm inside the petcock when the petcock is in the "RUN" position. When the diaphragm fails (and they all seem to eventually fail) fuel can be drawn past the diaphragm through that vacuum line and into the #2 carb making it run rich. If the petcock has the problem it must be rebuilt or replaced.

You can check the petcock a couple ways. Disconnect the vacuum line from the #2 carb. It should be dry - no fuel in it. If any fuel is present in the tube there's a petcock problem. Another way is to disconnect the vacuum line and cap off the vacuum nipple on the carb and the vacuum line on the petcock. Install a fresh spark plug in #2 cylinder, turn the petcock to Prime, and take a ride. If after riding a while the #2 spark plug is not wet the petcock diaphragm has a problem. If new plug in cylinder #2 is wet with the vacuum line disconnected the problem is probably in the carb. Ed