Looking over my newly purchased (2nd hand) 2002 620 I see that there are two bolts per cylinder head on the left side that come out and have open nuts on them. The preivous owner has applied rigourous amounts of engine grease presumably to avoid these collecting water/grime and seizing down the track. On a naked bike this is a magnet to grime. Has anybody found an alternative ? Can you get closed cap nuts that fit the shaft of the protruding bolts ? Has anyone else thought this was a problem ??