Advice before my first big race

Ok, so I will be doing my first duathalon this weekend (10k run, 40k bike, 5k run) and I have a quick question. Starting yesterday I have taken it pretty easy again tring to save my legs for the race on Sunday. Saturday is normally my long bike ride day, usually and hour to an hour and a quarter. Should I still do the long bike ride on Saturday morning, or should I cut that back quite a bit since I will have a long bike ride on Sunday?

I am hesitant to do nothing at all, but this race is longer than anything I have done, or will even do this year. I know individually I can do all the segments, just not sure if I can do them all put together. My goal is under 3 hours. I know that sounds like alot, but when I break it down that is what I come up with.

10k - 55-60min
40k - 1:15-1:20
5k - 30-35min

I am looking forward to it and I know either way, it is going to be a blast!