my B&M TopLight line brake plus

[simonineaston]

A couple of observations on the subject of the Busch & Muller dynamo-powered back light, in case anyone's interested. I inherited this lamp when I bought a cycle from another forum reader a while ago, since when I haven't given it much thought but yesterday as I cycled home in the dark I thought what a decent lamp it is! Benefits are:
* As usual with most bike lighting of German origin, it's reasonably well designed / built / bright. So far, so nothing special, but...
* The fact that it's working is readily visible from the saddle as it has witness holes in the back shell where the red light shines through.
* The advertised 'brake light' feature actually works! Apparently when the lamp's built-in circuitry detects a drop in output from the dynamo, ie when the rider stops pedalling, it increases its brightness in a way that mimics a car's brake lights. Whether or not potential buyers see this as something worth paying extra for is another thing.
* Lastly, it retains enough power to stay illuminated when the cycle has stopped - ie it has a standlight.
Hope that helps anyone thinking of buying one.

picture of B&M rear lamp

ps the odd-looking white strip at the top of the photo above, actually shines red.

[Jdsk]

...
* The advertised 'brake light' feature actually works! Apparently when the lamp's built-in circuitry detects a drop in output from the dynamo, ie when the rider stops pedalling, it increases its brightness in a way that mimics a car's brake lights. Whether or not potential buyers see this as something worth paying extra for is another thing.
...

Someone once told me that it detects the drop in frequency from the "dynamo". So decrease in road speed rather than pedal movement (or brake application).

I like them too. : - )

Jonathan

[simonineaston]

So decrease in road speed

That's so cool!
I couldn't really tell y'day evening. I tried to see how it worked, but to be honest, stop/ starting in central Bristol's cycle lanes, at 9 in the evening after a meal&wine, with friends, isn't the best circ.s for that sort of thing !

[rjb]

Some riders fit their rear lights on a spring so when braking the light oscillates creating a similar effect for following traffic.

[wheelyhappy99]

Excellent light. The pattern of light helps drivers judge distance too, welcome on straight country lanes with too many berks in Mercs.

[ANTONISH]

That "Z" in the middle hasn't anything to do with Putin has it

[rjb]

That "Z" in the middle hasn't anything to do with Putin has it

It's a target for the incoming Exocet.

[andrew_s]

The Z pre-dates Putin, and indicates that the reflector satisfies whichever German regulation it is.

It's virtually impossible to check how well they work on your own bike, but I did follow one once on a bendy Belgian cycle track, and found it sufficiently useful as a following rider that I got one.
If you do follow one note that the brake light coming on (presumbly powered from the standlight capacitor) means that the bike is actually braking, rather than is just thinking about it, as can happen with car brake lights.

[simonineaston]

whichever German regulation it is.

Remember the kite mark... ?
ps thanks to mod. for moving topic to the eminently sensible location of ...goods & services / your reviews