I would say something odd has gone on with the choke arrangement in the past by a previous owner for whatever reason, as the others have said a '97 900 should have it mounted between the switchgear and the clutch lever/mirror bracket like so:
As an aside, I have never had either the choke or throttle cables brake in my bikes' twenty two years.
Perhaps if it is regularly doing so then it is routed wrongly and maybe rubbing somewhere it shouldn't?