based on the gs tanks, I'd say it's an 80's era,
cause of the locking gas cap cover.

when you find out, don't be stingy.  

NVM,

1977-1982 model Suzuki GS series bikes and others all have similar styling  

1978 Suzuki GS750
http://www.pipeburn.com/home/2010/07/14/1978-suzuki-rat-bobber.html

thanks Bot,

I was looking to stay with Suzuki parts  

now to find one that isn't beat to death, rusted, missing the cover, lock and keys  

I know Justin,

I spotted one that a guy wanted $999 for, it was OEM NOS in the box and still wrapped all nice and purdy

DesertRat wrote on 03/28/16 at 06:59:56:


NOS means $$$!  

YES, $999.00 for the tank, still in the plastic and wrapping in a suzuki OEM factory box with all the labels and tape still there. I'll try to find the sale in my web history.