Strange things happened this summer as:
A colleague texted me his scooter, an italian brand, would run only intermittendly and is pretty hard to start.
Went there, tried, scooter started and run normal at first try.
Switched off, NO start.
-all the things checked like KILLSWITCH, SIDESTAND, FUEL, PLUGCAP, etc.
-sparkplug out (please see pics).
The middle elektrode was completely gone. It must have been fragmentarely there for a while to allow temporarely starts and run.
Ignition coil, cable and plugcap were in order.
I really don't know what caused that errosion.
Usually I saw such a failure on racing engines where mixture was too lean or the plug was way off recommended heatvalue.
