There were no visibility problems; it was 6 pm. I was on the brief stretch of Oak Street between Baker and Scott. Bicyclists ride these blocks all the time to get from NOPA and the Richmond to connect with the Wiggle and get to Market or Mission. The lane is not wide enough for both a vehicle and a bike to be safely side-by-side. Cyclists must, or at least should, "take the lane" and travel in the near-center to avoid getting doored by motorists who don't check before opening their car doors.
I don't piddle along when I bike; on Oak I'm moving, keeping pace with motorists. As i rode through Divisadero a car close behind me honked and then, without a pause, sped up for the near sideswipe. For several seconds as the Lexus invaded my space, I struggled to keep my balance. The driver kept going without a pause. Without realizing it, I had slowed. The next motorist behind me -- who had to have seen the incident -- honked several times to get me out of the way as well.
After turning onto Scott, I stopped and asked the cyclist behind me if she had seen what happened. I asked her if it looked like the driver was indeed trying to force me from the lane. She replied, "Definitely." She added that she was visiting the city and she wondered if this happened all the time.
I've been honked at and yelled at before while biking on our streets, tonight's incident, however, was a first. For me. I completed my errand and returned to NOPA with a new appreciation for motorists who share the road as needed and a new awareness of drivers who take the road at all costs.