"Porky" wrote in message
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Nov 10, 9:49 am show options

Newsgroups: sci.electronics.repair
From: - Find messages by this author
Date: 10 Nov 2005 09:49:32 -0800
Local: Thurs, Nov 10 2005 9:49 am
Subject: A Non-friction bicycle lights generator (dynamo)
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In this new generation bicycle light system

Back in the 50's-60"s, some Raliegh, probably British import, bikes had
a dynamo built into the hub of the front wheel. They would have been
far superior to the friction clamp-on jobs we had to use on our paper
routes. I wonder why that design was dropped. I had a used Raliegh
3-speed for a while, but it had the drum brakes instead of the dynamo.
They were not good brakes.

John Kogel

My British bike ( which was a Raleigh ) that I had when I was a kid in the
60's, used a hub dynamo on the front wheel, and a Sturmy-Archer three speed
gear hub on the rear wheel - worked by a twist-grip, no less, rather than
the old finger lever !! A lot of my mates had bikes with the old friction "
bottle " dynamos on them, and I couldn't believe how much pedal effort it
used to take to turn them, against how easy mine was. There was no
difference that I could detect, lights on or off. but I guess that there
must have been a little.

I also remember that some bikes - particularly those used by the coppers -
had a sort of cylinder fixed to the vertical frame section under the saddle.
This contained rechargeable batteries of some description. I guess they were
D sized cells. When you stopped pedalling, the lights continued to be
powered by these cells.

It occurs to me, on reflection, that rather than dynamos, these generators
were actually alternators, in which case, there must have been a rectifier
of some description, ahead of the battery pack. Back in the 60's, this would
probably have had to have ben a selenium plate-stack type ?

Arfa