True, the 12v bikes have their compliment of unobtainium parts, that can stymie the purist. For the non-purist crowd, there's not a lot about the `90s bikes that is really remarkable and they don't have the collector interest of the earlier models. IMHO, the earlier style carburetors are far easier to work with. So unless your goal is a purist-correct bike, the only thing really better about the 12v models is the engine...and those advantages can be integrated into a 6v engine. The once true advantage of a `90s era CT70 is the motor. It's convenient having all of the upgrades in a single package...12v/CDI, needle bearing cases, ball bearing cam & updated head, long rod crank assembly.
That said, there aren't very many of the 12v CT70 motors to go around and those are the only ones with factory-installed lighting coils. Fortunately, there's a big supply of cheap, used, 12v motors out there...CRF & XR 50s & 70s. Add a lighting coil (aftermarket) and you've essentially got a 12v CT70 motor. Take note and bid accordingly.
That said, there aren't very many of the 12v CT70 motors to go around and those are the only ones with factory-installed lighting coils. Fortunately, there's a big supply of cheap, used, 12v motors out there...CRF & XR 50s & 70s. Add a lighting coil (aftermarket) and you've essentially got a 12v CT70 motor. Take note and bid accordingly.
