Valve / Rocker / Tappet, Adjusting Screw & Nut, M8, 1200-1600cc
Often called a "tappet" these screws can mushroom and wear over time as they constantly tap the end of the valve to induce movement. The nuts can also suffer damage if over-tighened or the incorrect spanner is used. Both of these issues can lead to difficulty in adjusting the "tappet" gaps. So if you see any wear on any of your screws or nuts we would always recommend replacing with new.
This is a complete standard replacement M8 adjustment screw and nut as found on 1200-1600cc engines