I am rebuilding an 88 zx600 ninja.  THe problem is i just finished painting a replacement tank and low and behold the S-O-B has a leak.  I am most likely going to use JB weld to patch it but i was wondering if anyone had a better solution.  I would appreciate any help

Used tank on Ebay?  Where is the leak located?  How bad is it?

I used the stuff you will find when you click on the link below on my GS500.
http://www.caswellplating.com/aids/epoxygas.htm

If you follow the intructions that come with the Epoxy Gas Tank Sealer you should have no problems.  

Do not use JB weld!!!

might i ask why not to use JB weld ?

Quote from: bmcmahon79might i ask why not to use JB weld ?

Because JB Weld will only cover up the outside rust spot and will not keep the tank from leaking in another spot.

The fuel tank sealer I listed the link above  will seal the inside of the tank so that the fuel will not be in contact with with rust which will sooner or later ens up in your carbs which will cause your bike to run like crap.