Rear spokes corrosion

[Old tenere phil]

Hi I'm not even at my first service yet (due this week ) as the bike has sat for a few months due to having no spare time and covid restrictions..anyway took it out for ride and noticed the rear spokes have started to fur up with corrosion already.

 

I was told by dealer that the front spokes are stainless but rear wasn't when I enquired before buying but didn't think within months of sitting in a garage albeit with some condensation, it would start to rust so soon.

 

Anyone else experience this ?