Valve adjustments and shims

Hi all, so I have some fundamental questions about setting the valves. In most cases based on my reading here the valves wear and become tighter requiring us to install thinner shims. So, we go to the service manual and buy/trade for the smaller thickness shim. We use the table in the manual to decide proper shim thickness. So, I also assume the shims are hardened. Why are we not sanding the shims down to the required thickness? Heat and dump in cold water to harden afterwards? My manual states that my range is .005 to .015 mm on both intake and exhaust if I read it right. Why do we need the table to figure out which shim is next in the range? They come in .005 mm increments right? Just want to make sure I'm not missing some fundamental reason. A couple of my valves are in contact so in that case can't I just go .015 mm thinner than what I have now with the expectation that I will get in range? I just got my tool today and will be removing the tight ones. Thoughts would be appreciated, thanks Keith

The shims I have appear to be surface hardened, depth unknown. If you did grind through the surface hardening it would expose much softer metal which would wear too quickly. I would never grind a shim.

As for:

Heat and dump in cold water to harden afterwards?

You would not want to fully harden the piece because it would be too brittle and prone to shatter. There is a product called Kasenit which can be used to touch up surface hardening on a steel part but I would not try it on a shim.

My manual states that my range is .005 to .015 mm on both intake and exhaust if I read it right. Why do we need the table to figure out which shim is next in the range?

Because some people are not good at math.

Oh, I see the FSM says not to modify them. I looked at the table too, pretty user friendly indeed. I used the motion pro tool to remove one of my shims, boy I can say not the easiest thing to work with. Also was worried about the can contacting the bucket with the shim out so I reinstalled it. I had a 2.25 mm shim in there and it is in contact. The table says go to 2.15. Does that sound right? Also, is the factory style tool easier to work with? If so, where can I get one? Last question do I need to do anything with the cam chain tensioner? I didn't see anything about it for this work. Don't want to make rookie mistakes if I can help it. Thanks, Keith

Yeah....don't modify them, the last thing you want is a shim coming apart under load, they might find themselves in another location anyway, when I did mine I only needed two new shims, let me know what you need as I have a few laying around, (the Kaw dealer in Bremerton was less than helpful wen I went there). Having tried both tools I much prefer the factory one despite the cost $ 55 at Z1 Ent. 2.15 sounds right for a start. I don't believe cam tension is not directly related to shim wear but it's a good idea to adjust after the valves are done anyway as the cover is off. Don't forget to write down what shim size you have under every valve and the gap you set it at for the next time. There is quite a lengthy and heated discussion on valve gaps in another current thread, but what I have done is set my intakes at between 0.07mm. and 0.09mm. and my exhausts at between 0.11mm. and 0.13mm. as they expand more due to the higher heat they have to deal with, I am a proponent of "Middle of the Road" adjustment theory. Hope that helps.

Service manual states shims might crack if you mess with them.