shim thickness question...(valve check)

[LoneRonin]

Hey guys, I just did a valve check on my Ninja 250. All my exhaust valves were out of spec and I got around to removing a bunch of stuff and eventually getting to the shims under the buckets.
They have little numbered markings and when I referenced those to whats listed in the service manual they're pretty much the same thickness they should be...but the valves were out of spec. Is it possible they're all out of spec but the shims haven't changed?? I always thought they got pounded in and flattened out over time, but thats obviously not what happened here...any ideas? This is my first valve check btw at 32k and all intake valves were within spec.

 

[ThrottleThrow]

a little off topic and i apologize, i was thinking about doing a valve adjustment because my valves are wayyy out of spec, but everyone says the sv650 takes forever, how long did the ninja take from start to finish?

 

[HERBXX]

The shims dont wear, the valves do. ! Thats why you have to change the shims to get the clearance back .

 

[PeterTrocewicz]

Everything wears eventually, but the valves do recede into the seats. There is no specific size that the shims should be even from the factory, they are put in according the size that is required to bring the clearance to spec. The nice thing with the Kawis is that the factory service manual has a chart which tells you the thickness and part number of the shim required once you've measured the existing clearance. Honda just gives you the math:
Required shim thickness =(Measured clearance+Existing shim thickness)-Allowable clearance.
And be happy that your shims are new enough that the number is still readable, wait untill the numbers are worn off and you have to measure them.