I'd try the JB weld again for now... If you do it right, it works great and lasts until you find a more permanent solution... I bet the last time, the surface was not clean enough for the 'Weld to bond properly. Follow Civic's advice. Also, after applying the JB Weld, be sure to let the bike sit overnight in a warm place to let the cold weld cure completely.
I had a '99 Banshee which had blown a chain a while back, leaving both engine cases split wide open around the clutch actuator rod, and underneath the countershaft. A previous owner JB welded it back together, and since the break in the cases did not result in a structural weak spot, I left it alone. Rode the Hell outta that 'Shee until I sold it last month. Never leaked. Was it a permanent fix? Probably not. Did it work? I didn't have any problems.