The case does act as a heatsink, and there are a lot of electronic bits in there all getting warm during operation.

Do the basic checks on your charging system - battery voltage with the bike off, then switch on and switch on headlight and see what it reads.

If that's good, start it and check out the charging voltage - if it's gonna blow it up I suspect it already has, and a three minute run to do tests won't overheat it.

You could always disconnect the powervalve motor if you really are worried before doing the tests, that won't affect the readings.
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