TOPIC:

So... The KZ400 is running. I pretty much rebuilt the carbs (reused pilot screws & jets), put 'em on, & that's it.

She came with a Mac (I assume) 2->1, & I replaced the decrepit boots & airbox with Uni pods.

She runs, no question. I even took her over the Williamsburg Bridge into Manhattan today. Got up to 50, which wasn't real smart considering the ding in the front wheel & the age of the tires...

Anyway, that being said, she has a couple issues:

She puts out a fair amount of grey smoke when I start her after a couple days of sitting. Less if she hasn't been sitting, but still some.

With the idle adjust screw all the way out, she stilll idles at ~2k when warm.

Anybody got some pointers for me here?

Thanks,
-Kit

Does it continue to smoke once it's warmed up or just till then?
KZCSI

Does the 400 have the seal on the valve stem? The smoke can be from worn valve guides too.

Kit, Valve stem oil seals have a difficult funtion. They need to allow SOME oil past to lube the valve guides but not enough to allow too much that will leak down into the combustion chamber. If the valve stem oil seals are older, they tend to harden and allow oil to seep down and sit in the combustion chamber. This will show up when you start the bike as a big ol' poof of smoke. It doesn't hurt much unless the seeping gets excessive and then it will tend to foul plugs. I replace valve stem oil seals EVERY time I pull a head for any reason.

With the idle adjust screw all the way out, she stilll idles at ~2k when warm.

Sounds like its time to lube and adjust (maybe replace) the throttle cables before someone gets hurt.