Well I have fitted my cam belt cover. It is quite ugly but functional and i hope it works. It is made from layers of laser cut stainless sheet steel. Bent into shape.

It is designed to not let in rain with a lip.
I might add more rubber sealing to this end.

Allows cooling through a slit at the top of the recessed plate. I have made it so I can add automotive air filters to the appeture if dust becomes an issue. Hence the central 6mm nut.
The air then passes out through a lower and larger apeture at the bottom which is at lower pressure being behind the number plate. There are internal guards to stop pebbles and stones from getting in at this lower end.
Black to maximise radiation.
much larger internal space for better circulation.
I had to put in a spacer for the number plate holder.

it is just two metric 8mm screws to check the belt now. No need to worry about over torqueing

I would do it differently another time. Good learning exercise. I am happy with my prototype apart from the ugly factor. Just the cover part needs to be changed to give it a better look.

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