Ninja 250 = 5 years though only rode it for 2, just sold it last spring to a guy at work.
600 = August will be 5 years and it's not going any where for a LONG time. 1.) I love it, 2.) I can't afford a new bike and a car payment.
Erik on the other hand...
ZX9 = 4 years
04 ZX10 = 2 years (not quite)
99 CBR = 2-4 weeks
07 ZX10 = 2 years (not quite)
05 ZX10 = 3 months or so
He is the same with cars. I don't care, as long as he doesn't try to trade me in