Partitioning my 1 TB LaCie HD backup, running10.6.8 and 10.9.2

My backup is close to being full and I want a second one to be on the safe side having one die on me a while back. Should I, or can I, clone both and then use TimeMachine backups in those partitions? Also, I saw some discussion about Time Machine in Maverick not spinning down when using Firewire 800, so my 2nd question is if I eject my backup and then just disconnect it will it screw things up or would it be better to power down my hard drive before doing so?

Thanks,