I bicycle alot and in sections I will take up a whole lane. Sometimes it is safer to do so. no shoulder to ride on and narrow lanes. If I dont take the lane I get people passing me with inches, when there are 2 lanes each way and they could easily pass in the other lane.

(as a rant, this section of road has 2 schools on it and bike lanes that end between 1/4 and 1/2 mile in each direction. It was relined to be 4 lanes instead of 2 bike lanes, a center turn lane and 1 lane each way.)

Riding on the sidewalk any any decent speed is asking for trouble. I don't mean from people pulling out, they usually look. I mean people turning right in front of you. This is often a case of lockup the wheel or slam into the side of the turning vehicle.