There are an almost endless number of rides outside P-town. Gotta do the whole Springwater. Gotta do the Gorge--lots of different ways to do this. See some waterfalls. There is a great route up Cornell and Thompson fro NW Portland to Skyline and then out over the rolling hills, which can be as long as you want it to be. Not sure how much you like climbing, but Mt. Scott is a pretty darn good climb. Council Crest. Sauvie Island is fantastic. Super cool. On and on.
Have fun!!!!