How about gettin' a torch and brazing/soldering? Particularly with today's Egas I don't think any of the "glue" type stuff is worth bothering with...
I have never use any glue (specialized or not) for fixing leaks in gas tanks, but hear this.
I found Permatex Instant Gas Tank Repair in a Kragen Auto Parts Store, looked at it and saw that it is a putty 2 part. I already found that I got a low cost carb replacement and had no need for it to fix the leak that a carb had a fuel inlet which use a shoddy plastic part attached to the metal carb. I would have ended up using this to fix the thing, but now am interested if anyone has use the stuff. They say it can go on wet gasoline covered metal. Seems like the Marinetex only in the sense that you can apply it to material with water present.
I have use some glue called Seal-All that said gasoline, oil, and water resistant glue that I got also at Kragen Auto, but ended up not using it on the carb since I got a new one. I did however use it to totally coat a servo motor for hobby stuff and make it water proof around except where the shaft with the toothed gear comes out on top. Maybe I will see about using an oring somehow later to fix that too. Servo motors made water proof are very expensive. This stuff is quite runny and I let it coat and drip off and then reclaim the stuff and pour it over it again and again to get a good smooth coating.
Of the two I found that state repair of gasoline container, if I were to ever want to use it in the future, I like the idea of the putty as you can build up a surface.
Other, when I get the motor bike going and have more time see about getting strong enough servos to autonomusly take the motor bike out with out a rider on it. Balancing was the big thing as seen on one of the DARPA Grand Challenges, but actually they I think disqualified the riderless motor cycle as the event was for 4 or more wheel vehicles anyway.
