Often, there is more gravel or sand or other crap as you get closer to right edge of the shoulder. Also, potholes are more common at the edge of the road in som

Often, there is more gravel or sand or other crap as you get closer to right edge of the shoulder. Also, potholes are more common at the edge of the road in some places. The leftmost part of the shoulder is usually the clearest and smoothest. And if there are cars parked on the right, it's good to have some clearance in case someone throws open their door without looking. I'll try to ride as far right as possible, especially on a busy street. But those other dangers are quite real, especially once you've picked up a bit of speed. In the areas I ride, cars can't really go much faster than bikes anyway (except they accelerate faster). So the relative speed of a car in motion is less than all the stationary stuff on the right that can hurt me. My city has a lot of cyclists and bike-friendly roads, so drivers are relatively alert and used to slowing down for cyclists. As a driver, the only time I find cyclists annoying is when they ride on the roads without shoulders or bike lanes and take a whole lane.