corrosion

In need of some help and advice please.... My front (alloy, not spoked) wheel on my 2015, 5500 mile GS is showing surface corrosion - and spreading! Can I ask if anyone on the forum has experience and what they did - i.e. report to BMW. left it, got the wheel refinished? Clearly it looks...

My spoke nuts have gone rusty on a well looked after GS LC 2013 Question is, given there covered under the corrosion warranty, would they replace the wheels? Just as an aside I don't even know how stainless steel nuts that are never touched by a Allen key even go rusty after 14 months. And...