Found an old tank in the garage, help me ID it

I was doing some cleaning in the attic and found this old tank. It has no badges or stampings in it, so I'm at a loss. All I can find is T.S.K. stamped into the petcock

The fuel cap is a twist-on style with a rubber seal.
.

http://i148.photobucket.com/albums/s37/vgames33/DSC00460.jpg

http://i148.photobucket.com/albums/s37/vgames33/DSC00459.jpg

http://i148.photobucket.com/albums/s37/vgames33/DSC00458.jpg

http://i148.photobucket.com/albums/s37/vgames33/DSC00457.jpg

I want to say it's from a very old (mid 60's or so) Honda 50 or 90, something like that. The round spots in the sides are where the Honda emblems were back then, and the teardrops originally had rubber pads. That and the odd shape and cap placement all say early Honda small displacement bike to me. Probably worth something to a collector if it's not all rusted inside. Here's a pic of a '65 90cc I think that's very close. They changed the shape and size of the rubber pads on various model/years...

http://classic-motorbikes.net/images/gallery/90_s.jpg

That looks to be about right. I had a friend suggest an old Honda bike as well. The rear sprocket on that bike also looks like a solid match for the one I found with the tank.

It seems to be in great shape inside. Lots of varnish and some stale old gas, but no rust that I've noticed.

Thank you.

If you're still following this, we've batted it around in my cycle club, and it seems there's a high probability that it could also be from a Bridgestone...one I don't remember but I guess they were popular around the same time. I've looked at several pics of them and they strongly resemble what you've got there...

Ah Bridgestone.

I hear Ebay calling.
Look here, someone sold the same tank on Ebay last year for $46. (http://www.ebay.com/itm/1967-Bridgestone-350-GTO-fuel-tank-/230652556401?hash=item35b3f6b471&item=230652556401&pt=Motorcycles_Parts_Accessories&vxp=mtr)

Peter Egan, who writes for Cycle World and Road & Track had one back in the 60's, with the same rubber pads and little round badges with BS on them.

He got tired of people asking what the BS tags were so he turned them upside down. Then everyone asked what an upside-down BS meant. :)

I still pop in here to look from time to time. I appreciate the input. I've never heard of a Bridgestone motorcycle. Something new to research :smile:.