Camshafts strangeness...

Hello,

I measured the height of my KZ1000ST camshafts.


Here are the results, in millimeters:

IN: 36.11, 36.24, 36.18, 36.24
EX: 36.27, 36.27, 36.27, 36.27

Here are the values written in the KZ1000ST workshop manual:
IN: standard=36.21-36.39, service limit=36.12
EX: standard=35.71-35.89, service limit=35.62

So, one cam of the inlet camshaft is below the standard limit (36.11mm < 36.12mm). That's not cool.

But what's wrong with the cam heights measured on the exhaust camshaft? I
measured, re-remeasured, and each time I found the same values: 36.27mm on all cams.
That's *ABOVE* the standard height! It should be between 35.71-35.89, and it's 36.27mm!
It's definitely an exhaust camshaft, since there's a tachometer shaft on it.

How could that be the exhaust cams are higher than what is specified in the manual? Could that be a camshaft coming from another motorbike? Should I replace that exhaust camshaft?

Post edited by: Conti, at: 2007/03/26 14:47

Run them and don't worry about it....you don't have anthing that's going to cause a problem.

Service manuals are almost always suplemented with corrections after they are printed. You might be shocked to see how many errors are in OEM manuals...

what do the lobes look like, any pitting or flat spots , also look at the edges of the lobes, make sure the wear is even,

I'd vote just run them too. .1-.2mm is barely measurable. The engine wouldn't know the difference. I don't believe any of the KZs ever had camshaft wear problems.

perhaps special grind cams?? to exhaust just a bit more quickly? I am not a bike tech yet but that would be my idea. and yepp run it!

I took new measures last WE. I measured the camshafts journal diameters.



Here are the results, from left to right:
EX: 24,95 24,95 24,95 24,96 (mm)
ADM: 24,94 24,94 24,95 24,95 (mm)

So, the wear seems to be equal. However, one more time, the figures are completely different from what is written in the manual :


According to the manual, max diameter is 24.480, and that's 0.5mm less than what I measured!

I know start to have some serious doubts about those camshafts...

Moreover, when using some plastiguage to measure the gap between the camshafts and the head, I obtained around 0.38mm. Standard is 0.020 - 0.070 mm, and the service limit is 0.16mm.



The bearing inserts doesn't seem to be in a good shape. But I think the problem also come from those camshafts...

you aint gonna like this, plasti gauge lies too, I can make it do all kinds of stuff.

from what I am seeing, the lobes look to be in good shape, look at the bearings, if they are scratched up and wore looking, then replace them, I think you will be just fine

Perhaps I worry too much, I don't know...

Here's a picture of one of the bearing inserts:


Post edited by: Conti, at: 2007/04/10 16:34

Hmmm...
Don't know your background, but I would say that you really, REALLY like to measure things!
Just a thought...
Do you suppose that somebody has been inside your engine before, and they put an intake cam in place of the exhaust? Kinda looks like that is what you're measuring.
If your bearing clearances are in spec, I would conclude that the manual is suspect. Is it factory Kawasaki, or something like Clymers?

pstrbrc wrote:

Hmmm...
Don't know your background, but I would say that you really, REALLY like to measure things!

No, not really. :laugh: Indeed, I don't like to do this, but I really want to know the condition of the engine.

pstrbrc wrote:

Just a thought...
Do you suppose that somebody has been inside your engine before, and they put an intake cam in place of the exhaust? Kinda looks like that is what you're measuring.

That's definitely an exhaust camshaft, since there's a tacho shaft on it.

pstrbrc wrote:

If your bearing clearances are in spec, I would conclude that the manual is suspect. Is it factory Kawasaki, or something like Clymers?

That's the original one, edited in 1979 :

bearings look good to me, I would take a green scotch brite pad, some light oil, and a light buff, very light buff, just to clean off any scratches that may be on them , put them back in and reinstall the cams, replace the idler, check the valve lash, and run it

The scale on the plastigage reads (.038), not (0.38)
Looks to be within specification?? 0.38 is almost a half-inch!

Regards...