Sorry to probably ask a stupid question

I apologize to any of you kz and gpz veterans on my stupid question. I’m getting ready to put my engine back together (really just the cylinder head back on) and I’m looking for some shims online right now and I’ve looked at my service manual chart for valve clearance and can’t seem to understand exactly what it means, I need things spelled out for me cause of my slow brain. Anyways.... my bike is a 82’ gpz550 H1 and I’m just curious what a good clearance would be? I know it’s difficult to know through a computer but I’ve read 2.30-2.50 is a good size. I’ll assume they all can’t be the same and I won’t know what my feeler guage says until I put my cam shafts in, just trying to get a head start! Thanks!

.006" to .010"

No question is stupid when you don't know the answer.

It looks from your question that you're looking for a metric answer. Your minimum clearance is 0.15 mm and maximum is 0.25 mm. You should shoot for the high side of the mid point. It's OK to be slightly more than the max but not OK to be less than the min.

Thanks for the info! I really appreciate it

2.30 - 2.50 looks like shim thickness.

This snip is from the service manual. Measurements in mm.



Imperial measurements:
Intake: .004" - .008"
Exhaust: .006" - .010"

Curtismty wrote: I’m just curious what a good clearance would be? I know it’s difficult to know through a computer but I’ve read 2.30-2.50 is a good size.

This might be the source of your confusion. Shims tend to be around 2.00 - 2.50mm in thickness, and you choose the correct shim to bring your valve clearance to around 0.15mm for the inlet, and around 0.2mm for the Exhaust.

By way of example, lets say you measure the clearance of an Inlet Valve. Using your feeler gauges you measure 0.05. To get it within tolerance (0.10-0.20mm for the Inlet), you need to take off around 0.10mm from your shim (that would then bring your feeler gauge measurement to 0.15.

When you get your shim out for that valve, you measure it's thickness. Lets say it measures 2.30mm. You already know it needs to be reduced by 0.10mm, so you need to replace it with a 2.20mm shim.

When it's all back together, your clearance for that value should now read 0.15mm - right in the middle of the valve clearance specs.

When doing the valves the best way is to measure all the valve clearances and write them down. Then take off your cams, replace the shims that need replacing with the correct size, then re-assemble. Then measure again.

Here is what I found from previous post and from a way more experience dude than me. Original post is for a 750, but the procedures make it more understandable for the less experience people, like me anyway. Keep in mind that the clearance for the 750 is .10-.15mm for the example, but yours, like Nessisim says, is .10-.20mm for inlet and .15-.25mm for outlet..

There are two ways at least to check clearances. I don't have a KZ550 manual either, but the first thing to do is lock your automatic tensioner so it stays adjusted throughout the procedure.

The first procedure that is the generally accepted method you'll need the manual. You align a timing mark a certain way and check 2 valves. You need every available feeler gauge size from .01 to .25mm. Insert each feeler until you measure the exact clearance. Move the engine to the next specified mark and repeat on 2 valves, and so on until all 8 are measured, then take your readings and add or subtract shim sizes that are available in .05mm increments to get the correct clearances.

The other method that I was taught 30 yrs ago from a factory Kawasaki mechanic is you basically only need 4 feelers, a .05mm, .10mm, .15mm, .20mm. Lock your tensioner as in the other procedure before beginning work, then pick a valve to check. Turn the engine over slowly by the 17mm nut on the right end of the crank while you contantly try to stuff a .10mm feeler between the bucket and cam. If it goes, try a .15mm, if not try a .05mm. Find the largest in these feeler sizes that will insert during any spot in the rotation of the cam and call that your clearance. Repeat on each valve. Now you have all your clearances checked and all numbers make sense in shim sizes available, so calculating is no problem. So if you measured for an example .10, .10, .05, .15, 0, .10, .10, .10 you would see that chances are swapping a 1 size smaller shim in #3 would bring it to spec and increasing one size on #4 would do it there. #5 is the question mark and probably going down 2 sizes on it would do the trick.
The same engine checked by method #1 may read for example .12, .11. .08, .16, .02, .14, .13, .10 This just is checking too close as since the shims are only available in .05mm increments, the same exact swaps would be needed, just a different way to accomplish the same thing.

Irish Yobbo wrote: When doing the valves the best way is to measure all the valve clearances and write them down. Then take off your cams, replace the shims that need replacing with the correct size, then re-assemble. Then measure again.

This. You can move shims around and you won't know what shims you need until you are done measuring all of the valves. You may only need a few...
Don't worry about the dumb questions, most of us were in that position one time or another.

By Curtismty: ... I know it’s difficult to know through a computer but I’ve read 2.30-2.50 is a good size. I’ll assume they all can’t be the same and I won’t know what my feeler guage says until I put my cam shafts in, just trying to get a head start! ...

It sounds like you're wanting to pre-purchase some shims. Probably the best course of action is to check the clearances first, then if you have to change shims, figure out what's needed, then get the shims. This causes delays, but it's probably the best way to proceed.

I don't know that much about the 550. loudhvx has a valve train warning in his signature. just find any of his posts. Lou is kind of expert about the model line & has collected a bunch of info on his motorcycle stuff page. that valve clearance page is not for the faint of heart. :ohmy:

This might help. Just fill in the target tolerances info on the left, and your current tolerances and shims on the right. It will tell you what shims you need to hit the target.

1drv.ms/x/s!AutDGwoZ68krr4ERMcpyl0zC2QWuaw?e=vVYopp

If your brain is as slow as mine you will benefit greatly by getting a set of METRIC feeler gauges. The ones where it reads in metric primarily, not American whatever.
I finally bought a set and it saves you from doing a ton of math. The brand was Tusk.