Had the same problem too..fell out on roughroad and was held on by the wire ,damaged the rim of the wheel..
Fixed it with a bit of electical tape.
The rubber "o" ring is not quite thick enough..but be carefull there is a copper fing to earth it at one point on the rubber so dont cover that part.
You would have thought the dealers would be aware of the problem after fitting so many over the years..


Peter.
Aero plus8 50th Anniversary.