Valve Clearance question--is this unusual?

I am checking the valve clearances on my "new" KZ1000. This is my first time doing this with this type of valve (I've done my 440 before, but it doesn't use shims).

Cylinders 1, 3, & 4 were in spec, or at least very close--a couple valves measured .12mm, and I think I read here somewhere that being a little on the high side is not a big deal. The others all measured .08-.10mm.

On cylinder 2, however, the exhaust valve was not measurable--I couldn't get my thinnest guage (.038mm)in there. The bucket was turnable, so there was SOME clearance. The intake valve was waaaayyy high (.27mm).

I have ordered a shim tool from Z1, and am waiting for it to arrive so I can pull the shims to see what I've got in there. But I'm wondering if there is anything I should be concerned about with the intake valve clearance being so high?

Thanks.

Skyman wrote:

On cylinder 2, however, the exhaust valve was not measurable--I couldn't get my thinnest guage (.038mm)in there. The bucket was turnable, so there was SOME clearance. The intake valve was waaaayyy high (.27mm).

I have ordered a shim tool from Z1, and am waiting for it to arrive so I can pull the shims to see what I've got in there. But I'm wondering if there is anything I should be concerned about with the intake valve clearance being so high?

Thanks.

You could do a leakdown test at this point and get an indication of the health of the valve /ring seal condition. Guessing what \ why \ how, won't do anything for your peace of mind....

Larry C

Post edited by: larrycavan, at: 2006/12/09 08:53

suggest having a look at the camshaft bearings while it's apart...

FWIW my friends Ford Taurus SHO uses shimmed tappets. It's got 120k miles on it and the clearance has been slowly increasing since new. Evenly AND slowly increasing. Conventional wisdom on the kz is that the clearance decreases with use. Why the difference?

Post edited by: Duck, at: 2006/12/09 08:58

Valve clearances will go in either direction as engine wear takes place. There is no absolute certainty that valve clearance decreases with miles.

Duck wrote:

suggest having a look at the camshaft bearings while it's apart...

FWIW my friends Ford Taurus SHO uses shimmed tappets. It's got 120k miles on it and the clearance has been slowly increasing since new. Evenly AND slowly increasing. Conventional wisdom on the kz is that the clearance decreases with use. Why the difference?<br><br>Post edited by: Duck, at: 2006/12/09 08:58

Here's a post from an earlier thread.


Jeff.Saunders wrote:

Clearances normally decrease with wear and tear (although there are some exceptions - see below).

The wear on the valve/valve seat is great than the wear on the cam/shim/bucket.

If you have a valve guide / valve stem seal that leaks oil, the carbon build up on the valve/valve seat can cause the gaps to open up.

I'd rather hear the valves ticking than smell them burning... ha!

if you are really concerned about the excessive lash I would measure the height of all the cam lobes- just as a precaution to see if there is wear on that one camshaft lobe nose.

not probable but possible.. if cam lifts are all the same then get a thicker shim to get it into spec.

or not, more lash is better than less

KZ440 doesn't use shims?

guitargeek wrote:

KZ440 doesn't use shims?

Nope, see the following pic from kz400.com.

Besides the screw type rocker adjuster on the 440 which lots of bikes use, there are also hydraulic lifter bikes that require no adjustment at all... like the Vulcan.

I never knew!

THIS COULD JUST BE AN ERROR BY THE P.O.But as was said above you should take this time to check vales for a proper seal via a leak down or compression test.

Thanks everyone.

I will read up on doing a leakdown test and figure out how to do that next.

I bought a compression tester today. I don't have the bike running right now (carbs are off, waiting for new jets to arrive), so I wasn't able to warm it up. But I did a cold test, and the results were:

1: 145
2: 140
3: 125
4: 125

All within service limits, but I think you're not supposed to have >10% difference between them, right? I'll wait to do another test on a warm engine and see what I get, but are these preliminary numbers any cause for concern?