Aluminum oxide ???

[josh]

I stay away from WD-40 personally unless I'm using it to displace water. I recommended a product called Fluid Film.

[johan]

I wash my bike with turtle wax soap. NO I don't use hydrochloric acid. I liked to "rinse" the dust off the bike after work then wipe it down.
I've narrowed it down to the super hard water here at work sitting in spots. It seems in me being so "anal" with how clean my bike is has caused a problem. I used some simple green and a hard toothbrush and it came off...eventually
 

So it's limescale? In that case, hydrochloric acid might be just the...no wait, NEVER use hydrochloric acid on any motorcycle. 
Seriously, glad you got rid of it - enjoy the bike. Think of the dust as a patina (has a nicer ring to it than dirt).

[wessie]

Think of the dust as a patina (has a nicer ring to it than dirt).

 
He's learning...
 

[keithu]

You can definitely remove corrosion from aluminum, I did it every day for two years as a corrosion control tech on F/A-18s. And then I spent several years after that training Naval reservists how to remove corrosion from mostly aluminum aircraft. Follow these steps:
 
1. Is your bike still in warranty? If so, try to get the corroding parts replaced by Yamaha. If not, proceed to step 2.
 
2. Remove all corrosion from the part. Do NOT use steel wool or some other dissimilar metal. Bits of the steel will remain on the aluminum part and cause galvanic corrosion later. I recommend sand/silicon paper, non-metallic bead blasting, aluminum oxide cloth, or scotchbrite pads. Remove the visible corrosion product (white powdery stuff) and all pitting. My favorite tool is an aluminum oxide flap brush on a drill.
 
3. Clean the part thoroughly with soap and water. Rinse thoroughly and don't touch the clean part with your skin. Air dry the part.
 
4. Immediately treat the part with a corrosion inhibitor. Alodine is used in aviation but it's hard to find, so a zinc chromate primer will suffice.
 
5. Repaint the part.
 
 
Aluminum is highly prone to corrosion, but it can be repaired. You need to attack it quickly though, because unchecked corrosion will lead to stress cracking and failure of the part.
 
 

[Guest reeseyboy]

Good call.