Valve clearence questions

By the way. I think you forgot to add the link, Ed

Maybe this will help clear the air on this subject:

Here is the correct cover for a Kawasaki Service Manual that covers your KZ500-B3.


Here are the instructions for measuring valve clearances:


Here is the table for Inlet valves:


Here is the table for Exhaust valves:

noratx wrote: By the way. I think you forgot to add the link, Ed

Ooops. :blush: I went back and added it. Ed

And also just changing the shm from one valve that has a tight fit, or thicker size, from one of the valves next or across to a loose one....means nothing, because that shim is taking up the slack that grinding of that singular valve seat and valve creates.
All of them can be different #s and not just one size bigger or smaller.
You could have all kinds of different shims in there in order to get that FSM gap setting.
Make a chart up with each named valve and it's exact gap measurement and then remove the camshafts and remove the bucket and shim and write down exactly what number shim was in that exact same valve. Now you can use the chart to find the next number shim you need to widen or thin the lash gap.

noratx wrote: yeah, I edited the post shortly after, to go back on how positive I was

Anyway, I must ask though...
The cam shaft is round, only the lobe it making any difference.
The further away that the lobe are from the bucket, should tat not make for a more and securely accurate reading?
I mean, lets say the lobe is slightly more towards the bucket, that COULD make it so that you actually manage to measure .25 instead of otherwise .20

Just saying, considering the shape of the shaft, it makes more sense to measure with the lobe pointing as far away as possible from the bucket. No?

No. As I understand it the issue is not the shape of the camshaft. The issue is which valves the cam is pressing open. If they are adjacent to the valve being measured the pressure pushes the cam to the upper half of the cam journal and may give a different reading. Ed

This business about how to check the valves comes up all the time. The factory recommended method on how to position the cams puts two adjacent valves on the base circle at the same time, and then the valves are checked in pairs. This method avoids having the adjacent valve pushing up on the cam and skewing it in the journal clearance.

You can use the "point the cam lobe away from the valve" technique, but it's not as accurate and will result in the measurements being larger than if measured using the factory method.

Nessism wrote: You can use the "point the cam lobe away from the valve" technique, but it's not as accurate and will result in the measurements being larger than if measured using the factory method.

Very true. I re shimmed my 750-4 recently. I measured both ways, just to compare. Totally different measurements between methods. Journal clearance definitely affects valve clearance on a stationary engine.

I wonder if the factory method works as well with really long duration cams. At the point in cam rotation that the factory cam comes off the ramp, a long duration cam may still be on it, giving an artificially small measurement.

650ed wrote:

nessism wrote: I assume you checked the clearance using the factory Kawasaki specified procedure on how to position the cams right? If you pointed the cam lobe away from the cam and just checked that way you will get incorrect readings.

noratx wrote: "I followed the FSM I found and pointed the lobes 180 degrees away from the valve caps."


Really?? What FSM says to do it that way? I have a copy of the KZ400 / KZ500 / KZ550 FSM (Part #99924-1018-06) and my copy tells you to do it differently than that. Are you positive you are using a FSM (Kawasaki Service Manual)? Ed

+1
Ed is right on. The FSM speifies TDC position for checking clearance (on the 500/550).
Using other methods can give slightly different results.

VERY IMPORTANT: Also, don't install the valve cover until you release the tensioner cap and cross-wedge. Failing to do so can result in damage. There is a note somewhere in the manuals, but they are sometimes hard to find.

TexasKZ wrote: I wonder if the factory method works as well with really long duration cams. At the point in cam rotation that the factory cam comes off the ramp, a long duration cam may still be on it, giving an artificially small measurement.

That is a good point. You must follow the manufacturer's instruction on an aftermarket cam.

However, with just a mild increase, it should be ok. GPZ 550 cams are longer duration than standard KZ 550 cams, but the procedure is the same (uses TDC mark).

loudhvx wrote: +1
Ed is right on. The FSM speifies TDC position for checking clearance (on the 500/550).
Using other methods can give slightly different results.

VERY IMPORTANT: Also, don't install the valve cover until you release the tensioner cap and cross-wedge. Failing to do so can result in damage. There is a note somewhere in the manuals, but they are sometimes hard to find.

Yeah, I will take new measurements following the recommended procedure...
Just one question though, out of pure curiosity... what kind of damage can happen if I install the tensioner after I reinstall the valve cover?

The problem is with installing the valve cover after the chain is already tensioned. Notice there is a chain guide in the cover. This pushes down on the chain. If the tensioner is installed and at full tension, then you install the cover, the chain will be over-tensioned. This can damage the guides, stretch the chains, stresses the camshafts.

You can release the one-way action of the tensioner by removing the large (17mm) cap on the tensioner. This will allow it to retract when you install the cover.

If you already installed the cover, just remove the cap, and catch the spring and cross-wedge if they pop out, and reinstall everything. The tension should be normal then. Refer to the manual for details on how the tensioner works and should be re-assembled. However, the manual usually says to remove the entire tensioner. That is not necessary if you are not disassembling the motor. You will just have to deal with the tension on the chain (make sure the cap is off and the cross wedge is out or loose so the tensioner can retract) while reinstalling the cams. But once you know the tricks, it's not a big deal.

Similar problems can happen if you try to install the tensioner (the entire tensioner) while it is at full extension and unable to retract. So a tensioner, if you removed the whole thing, should only be reinstalled while the cap and crosswedge are removed.