I painted everything that sees water, dust, mud, ice, snow and salt on my 41 with POR15 some years ago (including the drumms in- and outside).
Now after this time I have to say I would do it anytime again.

Never had a heat problem with the drums, even here in Bavaria where we have lot`s a mountain roads.

POR15 can stand the heat on the drumms where other paints give up.

It is important that you make sure the metal is absolutley free of any grease.

And I mean ABSOLUTLEY!

I have best results with break cleaner or metal prep. Even a fingerprint can make the POR 15 come of like duct tape.

Belive me I learned that the hard way.

Frank