Just to throw in my 2 cents:
I already de rusted two tanks.one was awful (kz400).
I tried the electrolysis method...workes but not perfectly.
I did not use any mechanically abrasive methods and this is how i got it derusted perfectly.
I used phospor acid of the firm 'wagner'.
First de greased with acetone.filled the tank with 250ml of acid and warm water after one day it was spotless.
Then i rinsed it out with water.
Used alcohol...dried and used some resin of the same firm...worked a treat!
I already de rusted two tanks.one was awful (kz400).
I tried the electrolysis method...workes but not perfectly.
I did not use any mechanically abrasive methods and this is how i got it derusted perfectly.
I used phospor acid of the firm 'wagner'.
First de greased with acetone.filled the tank with 250ml of acid and warm water after one day it was spotless.
Then i rinsed it out with water.
Used alcohol...dried and used some resin of the same firm...worked a treat!