Here is a letter I wrote to the editor of the Almanac-News about the
basic speed law. It was indeed published. [I have made some minor editorial changes in this version.]
Too often we hear about crashes between motorists and bicyclists in which the cyclist is severely injured or killed. And when that happens, we also hear about residents of Woodside and Portola Valley complain about how bicyclists on narrow roads with blind corners represent a hazard to motorists.
I am a traffic engineer and a traffic safety expert. I have testified in many traffic accident cases in which motorists have unknowingly violated what is called the basic speed law. The California Drivers Manual says the basic speed law "means you may never drive faster than is safe for current conditions." The way this law applies to narrow, winding roads is motorists must not drive so fast that they cannot stop in the distance
that they can see ahead.
As you drive, imagine that just beyond the point that you can see there is a stationary obstruction in the road (perhaps a log or worse, an injured child). You must not drive so fast that you cannot stop before reaching the obstruction. It does not matter whether the obstruction is hidden due to a curve in the road or the crest of a hill, you must be able to stop. It also does not matter if the posted speed limit is higher or if your car can handle the road at a higher speed. You simply should not drive faster than is safe considering the distance you can see.
Those drivers who say that bicyclists in the road are a hazard because they are surprised by the cyclist and forced to take evasive action are violating the basic speed law. After all, the cyclist is legally allowed to take the lane when the lane is too narrow to share side by side with a motor vehicle. In fact, the legally riding cyclist is traveling in the same direction as the motorist, which provides even more time and distance than would a stationary obstruction in the road.
Bicyclists depend on the good judgment of motorists for their very survival. Cyclists are not interested in assigning blame in the case of an accident. They want the accident not to happen in the first place.
Bicyclists need for motorists to respect their right to use the road and for motorists to share the road in a safe manner. And that includes limiting their speeds in corners and over hills so they can stop if need be, according to the basic speed law.