I would never trust a bicyclist to stop at a stop sign; they're nutzo. I served on a civil trial jury involving a collision between a bicycle and a UCSC campus bus in twilight. Bicyclist did not have lights or reflectors. He said reflectors are dorky. It's Dan Palmer vs. UC Regents, Santa Cruz County CA, Feb. 2018. -- Gene On Saturday, April 14, 2018, 11:10:15 AM PDT, Keith F. Lynch <kfl@KeithLynch.net> wrote: Bike headlights, at least in brightly lit urban and suburban areas, are mostly for being seen rather than for seeing. The same algorithm could be used in reverse for them, aiming all their much dimmer light toward eyes. That would greatly increase the battery life, assuming the computer chips don't use more power than the lights. The light could also be directed toward anything dangerous that the cyclist might not have noticed, such as a fallen branch across the road.