Originally Posted by
FBinNY
No need to estimate a speed differential. It's 1 foot for every 10mph per their speedometer.
Since they're typically moving at 30mph or so, that's a 3' pass. However it's more at higher speeds, and allows for close passing at small speed differences on busy urban streets, though based on typical bike speeds, the passing cars are likely to be doing 20 at a minimum, so it's still 2'. If we're both crawling along in very heavy traffic, it might be as low as 1' at 10mph, but that's a very rare condition, and when it happens it's not an issues.
That is probably true. I thought NYC was gridlocked most of the time... so 10 MPH may not be all that uncommon. Or do the NY drivers mash the pedal the the metal between stop lights?
At < 10 MPH, the cars are as likely to get passed by bicycles (doing close pass lane splits) as they are to pass the cyclists.
Anyway, that is probably a good rule of thumb. Unfortunately, few lawmakers seem to acknowledge differing speeds. I can't say whether it is too complicated for drivers, but perhaps it shouldn't be, and they should be aware of their own speed, as well as individuals they're passing.