I want an Intelligent rear light

[goo_mason]

The problem with internal (and usually non-removable) rechargeable batteries is that they'll gradually lose the ability to hold a charge. If you want the security of a light that won't go out on you, why not have a 2nd rear light that runs on AA or AAA batteries? They run for weeks/months without needing new batteries, and you can keep a spare set of batteries in a saddlebag, or wrapped in plastic and taped beneath your saddle if you travel light.

A 1W Cherrybomb or a Cateye LD1100 would be idea (I've run both on my bike for many years - Cherrybomb on steady and the Cateye on flashing)

 

[mjr]

A dynamo can be unreliable and doesn't work when you stop.

The 1970s called: they want their myths back

As long as you can wire a simple plug (and UK mains plugs are much more complicated), current dynamo lights are more reliable than battery bike lights and "stand lights" are pretty common. Meanwhile, even the best rechargeable battery eventually gets to the point where a smart charger signals it as failing - and few bike light chargers even have that capability, so a dying battery usually comes as a nasty surprise like it has to the OP. The battery bike light market seems to be fuelled by madness, with people buying new iterations of the same old mistakes and hoping for a different outcome.

Just under the seat at the top of the post is the best place on my Brompton. I don't have to remove it when I fold the bike

I'm not rich enough to have a Brompton, but I'm pretty sure the back of the rack isn't impacted by the fold.

 

[Lonestar]

Well I use 18650 batteries and carry spares anyway,so no problem there.

I dropped AAA and AA's years ago as main power for my bike lights but also have a spare rear on my bike bag also.(Which takes AAA just in case of emergency/plus one on the bike there just in case)Basically I have four rears but only use two at one time.The others use 18650.My front are exclusively 18650.As are the spares in my bag.

Been down the dynamo route any times and even had hub dynamos.Had problems in the past with wiring and blown bulbs/slipping/worn dynamos...Just like now a bit of maintenance was needed to keep it in good working order.

Yeah got me bang to rights there as I recall my Brompton is fitted with a hub dynamo and now front and rear standlights unlike the old days of them going out when stopped.

Oh yeah plus LED's and not that filament bawlox.

The 1970s called: they want their myths back

Seinfeld classic,love that.

 

[LCpl Boiled Egg]

I'm not rich enough to have a Brompton, but I'm pretty sure the back of the rack isn't impacted by the fold.

I wouldn't know. I'm not rich enough to have a Brompton with a rack.

 

[cyberknight]

You need a hal 9000, just be careful it lets you back in ...............

 

[mythste]

I carry 2 spare lezyne femto in my panniers/saddle bag. Cost £8 aach and batteries last ages. Probably worth just buying new ones when they eventually run out! Keep a spare.