I thought I'd share a simple solution I put together to carry on my ST for transferring fuel from one bike to another. My sons and I have been involved in the R/C aircraft hobby for many years, and we've been using a small hand-crank fuel pump to fuel the aircraft. I picked up a version of the pump at the local hobby shop that's compatible with gasoline along with two 4 foot lengths of fuel line. It takes between 1-2 minutes to pump a gallon of fuel, which isn't bad at all. I like the "no batteries required" aspect of this solution. I carry it in a freezer zip-loc bag along with my Slime air compressor and tire plug kit.
Here's a link to the pump.
http://www.horizonhobby.com/Products/Default.aspx?ProdID=HAN155
Here's a link to the pump.
http://www.horizonhobby.com/Products/Default.aspx?ProdID=HAN155