21700 headlight

[Retrorockit]

Strobe penetrate the tinted windows on SUVs.. Strobes also light up crosswalks across busy high ways at night. Fast ones make it look like your bike is going fast. Those are the most annoying ones on the bike path. I keep them and put new batteries in them. I usually don't let my bike out of my sight. I do own the smaller lights for backup. But with a 24Ah battery run time is more of an issue than it used to be. I have one light with a replaceable 18650. I was looking at removing the battery holder and putting a 21700 in there. But it would n't work.My thinking on 21700 lights is they would be smaller than
2x 18650 which is what i'm trending towards at the moment.

[AZguy]

Well here's another where retro and I are likely opposites lol

I don't think I'd like the size of a 21700 light... I've gone the other way and using an 18350 (not 18650) light that easily fits in my pocket... it can also utilize 123 (primary or secondary) as a backup... Plenty bright or dim (5 levels from 1 lumen all the way to ~1000 lumens) - I usually only run 1 lumen to better keep eyes dark adapted and to avoid drawing attention or annoying others

Only use I have for strobe is when I *want* to annoy someone - not often - usually just for the idiots that run strobes on the multi-use where they are entirely unnecessary and super annoying...

[Retrorockit]

I own a few dual 18650 lights. They work well and are Niterider brand so pretty much a known quantity. But the batteries are not user replaceable. This light you just pop in a new 21700. It's probably the coming thing. But not mainstream yet. I didn't see much else out there, so not much comparison available yet.
I'm not saying this is a particularly good light.It may or may not be. I'm just pointing out that 21700 lights are becoming an option, and if run time is important to you probably worth a look.Acebeam does do 1060 lumens, and claims 2000 in Turbo.But I ignore the highest settings. I don't fing them as useful as the middle ones.

[stts]

waste of time

[Retrorockit]

I was repowering an old headlight with a new 18650 battery and got curious about whether there were any 21700 lights available. I did a search and found this one.

https://www.illumn.com/flashlights/acebeam/acebeam-bk10-2000-lumen-rechargeable-bike-light-21700-5100mah-battery-included.html

With a 5100mAh battery run time at 350 and 750 lumens is huge. 15h, and 6h. A nice lens and wide beam pattern. I don't own this (Too many Niterider lights already).

https://www.acebeam.com/bk10

They're calling the strobe setting an SOS. No idea what you'll get there.