Not particularly worrying apart from how it looks.
if it was mine I'd brush off any loose stuff and put ACF50 on it or at the very least GT85 (smells nicer than WD40) or even just wipe some oil over it with a rag from time to time.
I'm not bothered in the slightest by the looks does it form a protective layer? I would brush it off but then that might just leave new aluminium underneath to fur up
If you just leave it, the corrosion will get Far worse! I've seen crank cases with very deep pits in the alloy, which has scrapped the cases. Can't understand why peeps don't look after their bikes.
Forgive me for riding 6 days a week, 10,000+ miles a year and being a busy full time working man so not being able to look after my bike like its a temple to god.
As to acf50, it burns off on the hot engine so its kind of useless in that regard.
does it form a protective layer? I would brush it off but then that might just leave new aluminium underneath to fur up
Simply shocking 'maintenance'!!!!
ked.