I'm an ex-Portland commuter. I used to work in Sellwood and lived in NW. I often rode to U of P. If it were me, I'd take a longer, but more scenic and safer route. I'd cross the Sellwood bridge, ride the bike path along the west side of the river all the way to Front ave and continue to Kittridge. Cut over to Hwy 30 (generous shoulder for biking), cross the St. John's bridge, then take Willamette to U of P.