That really SUCKS !!!!
I guess it all depends on how much money you want to put into the bike, bringing these bikes back from a neglected life, can be costly at times, so it all comes down to if it is worth it to you or not in cost and effort.
I just put a little over $2000US into my '81 in the last 2 years , after owning it since January,'81, it's almost like a member of the family now !!!!!!!!!!!!!!
The current value of the bike is around $2500-3000, so it almost doesn't make sense to continue to put money into it, but I probably will, as long as I am able to ride it. .