On Sun, 10 Dec 2017 07:01:57 -0800 (PST), jbeattie
wrote:
On Saturday, December 9, 2017 at 5:58:56 PM UTC-8, Tim McNamara wrote:

The problem is noted by yourself right above. "With one battery
change at 6.5 hour burn time." I don't want to have to carry an
extra battery with me and then change it partway through my ride.

During the summer 6.5 hours is all night -- and that's at full output.

Depending on where you live. About true here in June around the
Solstice.

He says 36 hours "climbing" and long distance touring, which is code
for "going slowly." The output is probably a few hundred lumens or
less. I leave it to those who own the property to judge its quality
and value, but those numbers are more than I've ever needed. I do like
the convenience of not having to charge, and battery life is always
over-stated and diminishes over time anyway, but if you could get
those numbers in real life, that's more than 99.9% of people need --
and you can use it on more than one bike.

Being able to use the same light on different bikes is a legitimate
advantage. I have three bikes with generators, two of which (SON
hub/eDelux and Velological/eDelux II) were not insignificant investments
(the Sanyo BB generator on my commuter was free and the halogen lamp was
fairly inexpensive). Even a pretty expensive flashlight and multiple
mounts would cost less.

Ultimately the purchaser has to decide on cost/benefit. I don't want to
have to think about lights and just want them there reliably. I don't
care about the small amount of extra weight and have never been a gram
counter (at 6'3" and 230 lbs, gram counting is nonsense). The drag of
each of these systems is very low to the point of being almost
unnoticeable. To me the benefits of generator lights outweigh the
costs. The costs of flashlights outweigh the benefits for me. I don't
need searingly bright lights and the hassles of having to remember to
keep the batteries charged, carry a spare battery in some situatons,
switch the light from bike to bike, etc., are unappealing. For other
folks the math is different.