...as $$$ as tanks are, i would def try searching the web for a fix b 4 springing for a new tank.
1. first VERIFY that it is indeed a crack, or merely leaky gasket/s
2. try having it plastic-welded
3. most nail-polishes will seal well and is gas-proof for about a year. it also flexes some, unlike jb weld/epoxy.
4. ppg paints (and others) now make a gas-proof paint specifically for plastic surfaces; if u cannot find it, go to your local automobile paint supply store (where the body shops buy their paint). u can use this if your chic (or man-friend seeing as how u ride a honda) has no paint for her nails...
5. do NOT use silicon, as it has been my experience that even the copper flavor will ball up in tiny balls once immersed in gasoline for a time, wreaking utter havoc to your carb jets!
ttfn,
jks