goday binnsy,looks like white alloy corrosion ,used to get this on bus mirror brackets and to neutralise the corrosion we used a mix of lemon juice and vinegar if i remember right, cant remember the ratio,brush on let it sit a bit and rinse off ,ready to prime and paint. cheers
I used the el cheapo spray can Knights satin black.
Didn't burn off ?
No burning and seemed fine, I used it as it was an old can from another project, had it on a Dyna wideglide for about two years before I sold the bike. But if you don’t have anything laying around the satin engine enamel at Supercheap is only $17.
I can tell you the best way to treat it, but first you need to lick the area. Let me know if it tastes salty or sweet.