Now, look BEK155 has got a 1,8 8V with solid tappets, adjust with simms.
BEK, a little tapping noise will not ruin the tappets or cam right away, but you might have some tappets that are to close (will not make a noise) and thus burn the valves. You or a mechanic can check the valve clearance with a gauge (or tappet feeler). My Owners Manual doesn’t give the clearance for any model but from memory (from my former 75 2,0 single spark) I think it is: Inlet 0,4 mm, Exhaust 0,5 mm +/- 0,1 mm both; engine cold.
Hope this will help you, but, better check the clearance figures.