From PBOT, The Portland Bureau of Transportation:
The Portland area has lots of great places to ride. These maps help you to find the roads most suitable for your riding style & preferences.
Average daily traffic volume is shown, as well as roads with shoulders, type of road surface (paved or not), campgrounds, and major climbs. If you have comments or corrections for any of the maps, please let us know as we strive to provide the best, most accurate information for cyclists.