Originally Posted by
PhotoJoe
I am going through the same thought process. I found the
Electronics, Lighting & Gadgets forum and
this thread in particular got me thinking. I have to outfit both my wife's bike and mine with lights, so I think I'm going with the 26650 flashlight route. I'll order one first to see if it's enough, then decide how to proceed from there. The outputs are amazing for a $25 ebay light. Others will chime in on how it's not the best way, but I can outfit both bikes, with two lights each (if necessary) for a total of $100.
Check out SoCalRider's video
here.
I went a similar route, but with a 18650 battery flashlight. The light itself at the time (a Cree XM-L LED, they're a lot cheaper now) was around $50 and it's medium mode at 400 lumens gives me about 3hrs of life, the 750 lumen mode is really bright but is a little more than an hour. It's super easy to switch between bikes and I can use it for other things off the bike such as camping. For me it was hard to justify spending so much more for less light and battery life at the same price point. I can't even tell that my riding buddies lights are when we're side-by-side in the mornings.
Like PhotoJoe said, take a look at the Electronics, Lighting & Gadgets forum as there is a bunch of great information in there.