Join Date: Nov 2009
Location: Lander, Wyoming
The valve shims could be 2 or 3 different brands or even generations of production.
The numbers are to be installed down, so they don't get rubbed off.
Do the numbers all look like the same font? Really doesn't matter.
At 46,000 miles, your bike should be ready for its Fifth valve tappet inspection. (Break-in, plus 4 more.)
Your bike has apparently had properly oiled air filter service or it would have had more 'tight' valves.
Modify at "YOUR OWN RISK"!
Still riding my 1987 KL650-A1. 84,000+ miles & counting