not sure if this is the correct spot to post this but i was talking w a local motorcycle shop employee and i had questions abt the rust in my gas tank. he replied simply to remove and drain the tank, obviously, and to pour bb's into it and shake the hell out of it for a spell. remove bb's, powerwash inside tank, then using a compressor dry it well. anyone know of or have any luck with this procedure?

 

update to the BB theory.
stupid. it wasnt until i started shaking the fuel tank vigorously that i suddenly realized.....i am not a freakin paint can shaker. this may work well if the ability to shake the fuel tank other than by a human is available. now granted, the bb's did knock and collect a heap of rust, but the energy it took to accomplish this was not worth the trouble. live and learn.

 

Might not be the best way of doing it, but I used to remove the petrol tap(s) from my bike and, resting it on some wood etc I'd put a garden hose into the fuel filler hole and blast the tank around for a while, letting it all come out of the tank tap hole! Shifted the crud out for me. Leave to air dry overnight and check to make sure it is dry before refilling. Hope this helps!