A Non-friction bicycle lights generator (dynamo)

[:::Jerry::::]

,

So in that case cycles should not be using flashing lights either...

[John Rumm]

Flashing lights do not make for useful illumination for the driver - one of the key purposes of headlights on a car. This is rarely the purpose for cycle lights (and if it were, you would choose alternative/additional non flashing lights). 120W of flashing halogen light would be way too distracting and fatiguing for drivers surrounded by them - this is in a different league to a few high output LEDs.

Tail lights are a different thing again. They are there to assist in visibility but also in perception of distance and speed of the cars in front of you. Flashing would not aid this process. Tail lights are something that youll will have in you field of vision for the majority of most night journeys - again not something true of cycle lights.

Flashing rear lights are good at alerting following drivers to hazards and unusual circumstances. A person on a bike *is* and unusual circumstance (as a proportion to the bulk of the road traffic you will encounter on a journey)

They would not make for safer roads if fitted to a motor vehicle. They do make for safer roads for cyclists however.

[John Rumm]

There is a safety gain having them flash simply because affords you the economy of power consumption that makes the high illumination level you approve of viable.

[manatbandq]

It's all Jerry knows how to do when he's lost the argument.

MBQ

[Dave Plowman (News)]

They use less current. With an LED you only 'pay' for the actual light. With a flashing tungsten, the resistance gets higher as it cools, so the savings are less. The reason it was common to see kids on bikes with no lights is the cost of batteries.

[:::Jerry::::]

But it is, it might be more bulky but that is not the issue.

[:::Jerry::::]

EXACTTLY!

When cycles can obtain similar (if not faster) speeds around towns as motor vehicles then the same arguments apply surely?

Tail lights are

majority

Not even in towns and villages etc.?

hazards

Then they should have to use a flashing amber light, surely?

We will have to agree to disagree then, and you will have to disown your own arguments above!

[Rob Morley]

The resistance is lower at lower temperature. But as you've removed power in order for it to cool that's not really relevant, is it? The surge current caused by the initial low resistance when power is applied is what usually makes an incandescent lamp fail.

LEDs are an inherently more efficient way of making light from electricity - most of the power of an incandescent bulb is wasted in heat.

Was common? It still seems to be pretty common around here, and not just kids.

[Dave Plowman (News)]

Absolutely. Meant current.

Yes - it uses more current over the duty cycle than an LED which has no start up surge.

Well, car flashers seem to manage ok.

LEDs ain't the ultimate, though. It's mainly the lens which concentrates the light in one direction that makes them work well on a bike. They're useless for general lighting, though.

I'd say it's not as common as it once was. Could be it's now a fashion accessory and of course some are rechargeable.

[:::Jerry::::]

,

It's the flashing, not the light source that I'm against. LED's use less power than tungsten bulbs so even if they didn't flash there will be savings in battery life.