A long term project was to fit the timing cover with revcounter drive to my 1955 HS. After a little fiddling it went on well.
Before I went out for a test drive I thought I give the angle drive some attention with the grease gun. I might have put in a little too much. After about 1 km the rev counter stopped working.
Back in the shed I realized that the cover with grease nipple had gone letting the drive spindle move out and subsequently disengage. I thought "oh sh.."! So all I needed was a new cover which had been replaced by the specialist "KaJa" only 3 kms away over the weekend.
Imagine my surprise after I refitted the renovated angle drive I found the lost cover in the valance of the rear wheel. But on the left side! It must have jumped from the tarmac right into the rim. Hard to believe. I doubt that it can be repeated.