Also been down the road of fried rectifier, left stranded on the side of the road – anyway I replaced it and brought a second as a spare. Fits perfectly under the seat when the white air ‘thing’ is removed.
Now almost paranoid of it going again I decided to “help” it the best I could. Seeing it gets so hot and sits above the exhaust covered by a plastic fairing, this all seemed bloody stupid. I drilled holes in the top of the side panel to help air escape, fitted a heavy earth cable from the rectifier to the chassis and in a moment of madness cut down a copper finned computer graphics card, cooler; this is attached to the back with computer cooling paste.
I then fitted a battery charge condition LED, as used on microlights. Simple LED which changes colour depending on the voltage, I don’t remember the full range, but its something like red -11 volts, green 11-14 and yellow over 14v. The light is fitted to the dash and is a very simple way to see what’s going on.
So 9000 kms later, including the dead sea at 45°+ its all working fine, which part helped I don’t know but as a package it keeps me happy on the road (maybe it’s the idea of having a spare !! )