Originally Posted by
gauvins
..., research has shown that biomotion increases the probability of early detection (Edewaard 2017. The Conspicuity Benefits of Dynamic and Static Bicycle Taillights at Night). The authors write that heel-mounted lights were detected at a distance 5.5 greater than equivalent non-blinking seatpost lights.
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I have put reflective tape on the crank arms on most of my bikes. Initially had enough tape for only a few crank arms, but a few months ago bought more tape and now have it on front and rear of both crank arms on most of my bikes. Pedal reflectors would be better, but SPD type pedals are not designed with that in mind.
I have no clue if it helps at all during daytime on an overcast day, but most newer cars have headlights or other front bright lights on during daytime so maybe it will help a bit?
After decades of commuting on a motorcycle, I am convinced that on a sunny day, visibility is not a problem, but on an overcast day a motorcyclist or bicyclist should behave as if they are invisible to all car drivers. If you can't see your shadow, that is an overcast day when you need to be most careful.
Half a century ago, leg lights were popular for bicyclists at night, a two C cell light you strapped on your left leg, front side had a clear lens, aft side lens was red.