Nick Payne said:
A couple of times I've used my HDS Basic 42 as a bicycle headlight for commuting with a rubber mounting block to fasten it to the handlebars, but the primary 10 lumen setting is not quite bright enough and the runtime on the 42 lumen max setting is not quite long enough to get me home (it's a 25 minute ride).
Well, you could consider it an excuse to get an Ultimate so you can change the brightness settings. FWIW, the U60, U60 XR and U85 are more efficent than the U42, so they should run a lot longer at 42 lumens, than the B42.
The manual for the flashlight says that there's a 2xAA battery pack available as an accessory, but it is not shown on the HDS web site as an accessory. It this just vapourware or not? A 2xAA battery pack with 2500Mah NiMH cells would get around the runtime problem and also be considerably cheaper to run, and when used as a bike headlight the increased size and weight doesn't really matter.
Yes, it has been well discussed on the HDS forum of CPF and is generally accepted that they will show up, but the big question is when. Last guestimate is Jan., but some are betting Feb.
A couple other things to consider.
The 2x123 battery pack is likely to make the light run 4x longer, not 2x. So, going to a 2x123 battery configuration is going to be useful in terms of runtime, regardless of if you decide to stick with 123A cells for this application or not (although I admit, rechargables sound like a better fit). One caution tho, 2xR123 is not supported.
That said, I think there is a better option for you than the 2xAA pack. The 1x18650 battery pack. As I understand it, the 18650 is a lithium-ion that is basically the same size as 2x123 cells (but a tad fatter) and has better runtime than 2x123 cells.
I'm sure the folks who know the B42 runtimes better will chime in here with more exact numbers, but I suspect it should net you somewhere better than 60 mins on a charge at 42 lumens (assuming a conservative 4x increase over a pessimistic 17 min runtime on max = 68 mins).
I think HDS is planning on selling an 18650 batter + charger kit, but you can also buy them from
AW.
Even so, the 2xAA battery pack seems like it would be useful, and I'll probably be getting one anyway, but the 18650 seems to be the sweet spot.
-john