| Well you should consider getting a proper service shop to look after your bike properly or take it to the spanners yourself. One step in the servicing specifies "verify tightness of all bolts". This was probably not done...
As for the oil pressure switch it should have come up with a warning red light well before bursting open???
I have never lost a number plate or mudguard on my 748 and not even on my 996 (that has more vibrations), but then again I check those things or I get Nelly to check them! | 
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