OEM Cam Chain sprocket

93,300 Kilometers.......with a "bolt" modified OEM C.C.T.(using the OEM spring) 

 

That's not pretty at all... 

Holy Crappers Scotch. you turned an "outtie" gear to an "innie" gear.
 
the top gear in pic is a brand new Kawasaki tensioner gear
The bottom gear is a tensioner gear that came out of my KZ1300 at 42K  Km.

Is this from your bike scotch?   Did you mention a while back that you intended replacing this sprocket with a steel alternative?

Have you ever carried out a compression or leak-down test. on your engine? I just wondered how it is fairing after 90k km.  Does the bike feel as powerful as you would expect?

I've been putting off replacing the sprocket  for the past several years but it's worn-out now. This year I noticed a "lack of enthusiasm" from the throttle.    Rings-n-valves, now, as well.  
Cylinders glazed like mirrors!   No scratches or flaws.  No ring-ridge. Piston-domes are pretty sooty but otherwise in excellent condition. Valve-stems have some coke build-up.  
Having the cylinders done properly at a machine shop. Hoping a precision honing will be all that's required but have a "Plan B" if  required.  Will have to see what lapping accomplishes.  I don't want to start cutting seats and grinding valves only to end up in the nightmare of not having enough clearance for even the thinnest shims.
Was going to wait 'til this winter but who can ride is this smoky crap.  This morning;  25 steps to my shop and my coffee had ash and burnt Pine needles floating in it !

I can't imagine how bad the air quality is over where you are. We have air quality alerts here in Port Perry Ontario and it's from the smoke coming from your end of the world. You're 3839.4 Km west of me and your smoke has us stuck inside!! 

Getting the valve seats cut and valve faces ground should cost you about .3mm on the shims ONLY if the shop doing the work knows that you're bound by the shim allowance and takes off minimal material, So if your shims are now at 2.60mm or larger, you should be fine.
I was in a similar situation and had the valve seats cut. The shop wasn't paying a great deal of attention and cut them too deep. In order to make up some shim allowance, I ordered new valves. Strangely, the new valves only bought me .1mm in shim thickness so the only "Fix" was to start replacing the valve seats in the head and when I get the machine shop to cut the new seat faces, I'll instruct them to cut them so I start at 2.80-2.90 mm shims. That way I'll be able to reface several times before seat replacement.
I think Kawasaki machined the new heads at the factory to fit 2.50mm shims and left us with nothing for a machine shop valve job. Makes me mad to think that  they probably did this intentionally.