Thanks for the info!
I just did google mapping, and i think i got it right:
65 Cahill St (San Jose Station) to 995 Hellyer Ave (apprx address...i'm just BS'ing) is 8.3 miles.

hmm i was thinking about riding caltrain but junioroverlord's comment is starting to make me change my mind - weather permitted, i might do the full ride from SF to hellyer just because...i can.
(plus i haven't done any long ride since the last SF-SJ ride)