There is a range of shims available, from 1.20 to 2.50 in 0.02 mm increments.With what it can be connected? If we take into account that the gaps are only adjustable to a smaller size, by replacing the worn tablet...
Although they do get damaged by valve stem in the Tornado by the 1000 N springs, the normal wear is the erosion of the valve - valve seat, which will reduce the gap - a.k.a. valve recession.
The hammering of the valve stem creates an indent, that increases the gap.
You can only tell what's going on by removing the cams to gain access to the shims.
In the past, knowing that the shims will indent, I have set the gaps to be on the small side, expecting the gap to grow. The hammering hardens the shim, reducing the gap growth over 5 - 10,000 km. If you can get to 10,000 without the gap going out of spec, it'll stay in spec for another 10 to 40,000 kms.
Precision Shims, in Melbourne, now have a 'D2' shim hard enough to withstand the hammering abuse, but you have to ask for it specifically. With these shims, I set the gaps mid-range. The only gap movement will be reduction due to valve recession.