Originally Posted by
Staypuft1652
Nothing you buy is going to run 3 hours in high mode, medium probably. 10 hours low maybe or with extra batteries. For 40 mph you also may need something with a narrow beam.
^^^^
Kudos also to O.P. for considering this
Very important issue.
It's not just about the Lumens
At 20+ mph you need a 'Thrower' , tightly focused and aimed far enough 'Down Range' to give enough distance to react to the hazard.
40 mph? Minimum 3hr run time? " none of that $100+ nonsense ". IMHE? YYeeaahhRRiight. Pick any 2.
As a year round commuter, my personal standard is, will the headlight/s enable me to see a thumb size to approx broom handle diameter 12 inch long - Dark Brown stick - laying on black wet pavement far enough ahead to avoid running over it and subsequent jamming into the spokes.
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