[blink.]

Friend brought over his 96 zx-6r because it wouldn't fire up, He said the bike has sat for about 2 months, I then pulled the tank to drain it and when I pulled the gas door off the tank I was greeted with this almost cement like crust, any ideas what this is and what caused it?

 

[or10r]

Oxidized aluminum?

 

[Kllongbrake]

ethanol will attack raw aluminum. I would think it would need to be E85 and longer than 2 months though. Definitely something got in there and had a fight with the fill cap...and won.

 

[SpazOnaZX]

Multiple metal types subjected to over 20 years of vibration, heat, and volatile chemical exposure. Corrosion is the big part of it, but deposits from fuels and the atmosphere are in there too. While that's pretty extreme for build up, it's not an unusual corrosion type as far as I've seen on gas caps.... If it was never cleaned it would eventually get that bad.

 

[blink.]

Got it, thanks for the replies...I prob won't bother cleaning it off just gonna trash it and get him a new one.