I had an XS650. We got it for free. Never got it running. It was decidedly old-school. Good luck finding a Bultaco. Period. It should also be noted that "pre '80s motorcycles" are generally thrashed to shit, which is one reason the overwhelming majority you find are R75s and XS650s that have been hiding in a barn for 20 years (they made a screaming million of them). It should also be noted that the technological improvements in motorcycles between 1978 and 2008 are roughly equivalent to the technological improvements in cars between 1958 and 2008. I've balanced Keihins. I'd much rather hook my RS232 port up to my Athena fuel injection and tweak the injector trim.' It should also be noted that $3000 will generally buy you a 2011 Ninja 250, which is safer, easier to maintain, faster and more pleasant to ride.