Update: I rode over this spot today. The signal for the cyclists is in fact before the real stop line. So the car was parked in the wrong place, sure, but it's not a bike box.
There is however an real bike box now at Scott in the wiggle in San Francisco.
Today I was riding east down Evelyn from the Mountain View Caltrain station. Frequently on this route I will then take a left on Mary to get onto Central Expressway to head to work. The left turn there has an advanced stop line for cars with a triangular spot for bikes to set up their turns. There is a lot of value for a bike to make this left turn from the front of the queue because you need to be able to set up a proper line as you turn left, so as to be able to take a straight line over the Caltrain tracks.
This morning, I wheeled up to the bike box and there was a car pulled up past the stop line and into the bike area.
I sent this out in a tweet and Fritz asked "There is a bike box there?". I had to think about this - my kneejerk reaction is "Yes", but is it a legitimate "Bike Box" - e.g. is the striping done like that specifically for bikes? I thought I recalled there being a bike symbol painted there - the tiny bike symbol with the vertical line through it to indicate where the bike sensor is in an intersection, but I wasn't 100% sure. I figured I would take a look at the Google Maps and check it out.
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Amusing. There is a car stopped in the bike box in the Google Satellite View, on the left side of the intersection. You can see how the striping is set up if you look at the right side of the intersection showing the left onto Mary from WB Evelyn. And no, that car is not in the process of making a left...
You can look at the ground there in the streetview picture, I don't see a bike marking. I'll have to go check it out again. What is clear, bike box or not, the first line is the stop line.
Not the first time I've ever seen a violation captured by Google....
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Global heatmap overlay on your bike route
19 hours ago