Originally Posted by
Spoonrobot
Blinding motorists is an issue created in the minds of Bikeforums posters.
It is myth (which unfortunately too many cyclists believe), that lights with a conical beam pattern (i.e. lights without a cut-off) do not blind motorists (or other cyclists or pedestrians). I guess you never gave your light-setup to a friend and made a self test with respect to blinding, haven't you? There is a very solid and good reason why passing beams/dipped beams in car lights have a cut-off. It is near on impossible to adjust a conical beam shaped light in such a way that you don't blind others. and if you do adjusted it non-blinding, the first 2-4 m in front of your bike are heavily overexposed, rendering the high power light useless...
Originally Posted by
Spoonrobot
Why would I shine my light directly at motorists or in their eyes? The light is mounted right side, slightly below the fork crown and aimed to project the hotspot ~75 meters ahead.
If this is a conical light, it is inevitable that it blinds others. Unless the light has a very narrow beam angle (say <10°), but that'd make it mostly useless for cycling.
Originally Posted by
canklecat
I've actually had drivers and passengers roll down their windows and thank me for using extra lights, especially the helmet blinkies. Helps them to see me better. And it helps to judge distance, speed and relative orientations better. Same reason why motorcycles are generally easier to "see" despite being narrow -- the extra lights offer a better handle on quickly estimating distance, orientation, speed, etc.
Did you mean that two lights make a cyclist better visible and help others to judge distance and speed? Or did you mean
blinking lights helps others to judge the distance to the blinking light source? The latter is false. One needs a constant light source to be able to judge speed and distance. Blinkies only attract attention, but make it very hard for others to judge speed and distance of the blinking object.
Originally Posted by
Leisesturm
I also agree that the top of helmet location is prime real estate for mounting a light to see with.
That is usually true when trail-riding, but not necessarily when riding on streets, unless they are very curvy. A light for commuting on roads/bike paths is best mounted on the fork or bar and should have a cut-off.
List of possible cut-off lights with decent, usable output that helps to create respect from car drivers: Ravemen
PR and CR series, Fenix BC25R and BC35R, Outbound Lighting Focal Road, Lupine SL, SL-F and the coming SL-X, Supernova M99 Series, B&M Ixon Space (Lezyne also has some pretty ok StVZO lights, but i don't know whether those are sold in the US/Canada)