what is normal frame rust?

I think it pretty much comes down to just where you live

What one might call normal

 

That's nothing! Mine is ten times worse and keeps passing the dealer's inspection. My gas tank skid has rusted off, but the key failure areas on the frame are holding up. I'm under warranty for two more years, so I have the dealer check it every time I'm in.

Come up to the snow belt if you want to see some worrisome rust. It's got me almost ready to bail on mine while there is some warranty left for a new owner. Otherwise, I'll keep it until it falls to pieces.

 

Mine looks about the same, it's lived in the SF Bay Area all its life. Barely any rain, humidity, or moisture.