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Old 04-08-12, 01:29 PM   #1
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Signal light on Arguello at Balboa in SF

In light of the recent bicycle collision that resulted in a pedestrian death, does anyone have a problem crossing the intersection on Arguello at Balboa? I've only started riding up and down Arguello as part of my commute. I've only done this a maybe twice so far, but I've noticed that both times I've been able to enter the intersection on a green, have the light turn yellow, and then red before I'm able to safely reach the other side.

The distance I need to cover is about 35m going south and 43m headed north. My mean speed is around 11 MPH, about 5m/s, based on my time to get from Ferry Building to SI; about 9 mi in about 50 minutes. I don't know what is my mean speed not accounting for stop lights or signs and such.

I guess the contrast here is that the intersection has far less pedestrians than Market at Castro and that I don't have the ability to reach 35 MPH on that section of road.

The yellow line is 35 meters. Going the opposite way, the distance is 43 meters not including the width of the far end crosswalk which is about 3 meters.

Last edited by jsdavis; 04-08-12 at 10:50 PM.
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Old 04-08-12, 09:33 PM   #2
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The light might not be properly timed. I think per code it needs to stay yellow for x amount of time. I think this is the table:

Going 15 mph it should take you about 6 seconds to cross 120 feet. Which still leaves you around 2 seconds short, if you just crossed the sensor line.
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Old 04-08-12, 11:08 PM   #3
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I have that problem with nearly all the lights on my commute (in San Mateo). If I start pedaling as soon as the light goes green, it's red before I get to the other side of the intersection.
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