I eat my R6
Join Date: Dec 2014
Location: Southwest Ohio
Bike: 2008 Yamaha YZF-R6s Stock
Re: White Dust around Exhaust Pipe
When aluminum "rusts" or corrodes, instead of showing up as reddish-brown, it shows as a white powder. I see a lot of this white powder develop on my engines that's not just road salt. Aside from that, some fuel additives can leave behind colored residue. One particular cleaner I used would color the oxygen sensor with a reddish hue. (like Mars)
As Broke suggested, check your plugs if you're concerned.