SON et Lumière

Just zis Guy said:

Tonight I used my new SON dynamo. I'm trying really hard not to get carried away, but I just have
to say how absolutely exceptional this dynamo is!

Yup, I've decided all the best bits of bike kit come in the form of hubs. SON dynamos are great, as
is my new toy - a Rohloff Speedhub. The worrying thing is I now have both hubs in use with wizzy
bit of kit. I suppose I might have to get a trike just so I can get another exotic hub of some
flavour :-)

In uk.rec.cycling Just zis Guy said:

Tonight I used my new SON dynamo. I'm trying really hard not to get carried away, but I just have
to say how absolutely exceptional this dynamo is!

I'm trying really hard to say 'what took you so long?' :-)

Quoted message said:

First, all those people who say you don't know it's there - are right! You don't! I connected it
without a switch as a temporary measure while I wait for the switched SON E6 lamp and even with
the front lamp beaming away there was no noticeable drag.

The drag certainly isn't noticeable when you're on the move, even at very low speeds, although I
don't have the version with the disc mount - I assume that you have. Indeed, you're only likely to
notice it if you switch the lamp on and give your front wheel a spin - even so, it'll take a while
to stop. I've managed to convince at least two people that the SON dynamo is a worthwhile purchase
just by doing the front wheel spin :-)

I'd be interested to hear how you find the E6 lamp when you get it.

Simon
--
Simon Ward, Accent Optical Technologies (UK) Ltd., York, YO31 8SD, UK "Perl is the ideal tool for
the inspired slacker who'd rather sing and dance than spend longer than they need to at work ..."
- perl.comhohoho.htmlOpen ↗

"Just zis Guy, you know?" <[email hidden]> wrote

Quoted message said:

Second, it is noticeably better than the Shimano Nexus. Same light, a Lumotec with 3W Philips
halogen lamp, but markedly brighter and whiter. Not sure if this is down to the automatic switch
on the Nexus or not.

I have heard that the Shimano switch has diodes in it that are overly-conservative, cutting off
peaks of voltage that a decent bulb should be able to stand. I can verify that a decent bulb doesn't
need this protection, as I have the Nexus. dynamo hooked up to an old Sturmey-Archer lamp with no
regulation whatsoever and haven't blown a bulb in a year of use.

The data I have from the older SON and first version of Nexus hub shows that the SON puts out a bit
more power than the unswitched Nexus, which in turn puts out more than the switched Nexus. What it's
like for the modern ones, I don't know. myra-simon.comdynotest.htmlOpen ↗ I tend
to recommend using the Nexus dynamo without its switch, using instead the switch built into a
Lumotec lamp.

Quoted message said:

I still like the Nexus and rate it highly, but early indications are that the SON is worth every
penny of the extra money. And did I say how good it looks? It's art for your bike :-)

I have one of each and am not really sure the SON is worth the extra money. I simply don't notice
any difference in light output or drag.

Hub dynamos definitely are tops though!

-Myra

Myra VanInwegen wrote:

[of Nexus and SON]

Quoted message said:

I have one of each and am not really sure the SON is worth the extra money. I simply don't notice
any difference in light output or drag.

Yes, it's hard to make the comparison when they are on such different bikes. But I have been hugely
impressed with the SON. Especially the quality of the casing :-)

--
Guy
===
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Myra VanInwegen said:

I have heard that the Shimano switch has diodes in it that are overly-conservative, cutting off
peaks of voltage that a decent bulb should be able to stand. I can verify that a decent bulb
doesn't need this protection, as I have the Nexus. dynamo hooked up to an old Sturmey-Archer lamp
with no regulation whatsoever and haven't blown a bulb in a year of use.

Doesn't it depend on what top speed you do? Could an unprotected bulb survive 45mph in
these systems?

~PB

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Doesn't it depend on what top speed you do? Could an unprotected bulb survive 45mph in these
systems?

It may or may not survive - but its life would be shortened.

If Myra is right and Shimano are more conservative with the voltage rating of their clamp then the
light may be dimmer but the bulb will (on average) last longer.

(First law of thermodynamics -- you don't get owt fer nowt)

T

Myra VanInwegen said:

I have heard that the Shimano switch has diodes in it that are overly-conservative, cutting off
peaks of voltage that a decent bulb should be able to stand. I can verify that a decent bulb
doesn't need this protection, as I have the Nexus. dynamo hooked up to an old Sturmey-Archer lamp
with no regulation whatsoever and haven't blown a bulb in a year of use.

Pete Biggs said:

Doesn't it depend on what top speed you do? Could an unprotected bulb survive 45mph in these
systems?

This is on my fixed gear bike which has never gone above 30mph, and rarely goes above 18mph. So I
don't know how it would tolerate high speeds.

-Myra

Pete Biggs said:

Could an unprotected bulb survive 45mph in these systems?

Probably not - but few will be unprotected. The SON has current-limiting electronics (or so I'm
given to understand), and all the best lights have built-in zeners anyway.

Guy
===
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Just zis Guy said:

Pete Biggs said:

Could an unprotected bulb survive 45mph in these systems?

Probably not - but few will be unprotected. The SON has current-limiting electronics (or so I'm
given to understand), and all the best lights have built-in zeners anyway.

My LightSPIN has a notice saying not to exceed 30mph for any significant length of time while using
it, presumably because its current limiter may overheat in those conditions.

Tony W said:

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Doesn't it depend on what top speed you do? Could an unprotected bulb survive 45mph in these
systems?

It may or may not survive - but its life would be shortened.

If Myra is right and Shimano are more conservative with the voltage rating of their clamp then the
light may be dimmer but the bulb will (on average) last longer.

I've just fitted one of these shimano hubs. It's early days, but so far, so good. As far as the bulb
goes, I've been running the same 3v bulb on bottle dynamos for over a year now. Admittedly it
doesn't get *that* much use, but considering how often the light gets put on/taken off the bike, and
gets thrown around in bags etc, I'm well pleased so far.

One thing I did notice that other day was the extent to which the spokes 'bend' at where the spoke
meets the nipple on a 26" wheel. The hub is quite big <and heavy!> and on a 26" wheel, to my eye,
there's a kind of twist at where the spoke goes into the nipple. Anyway, still rotates true
enough! Does me.

bob

bob

Bob Flemming said:

One thing I did notice that other day was the extent to which the spokes 'bend' at where the spoke
meets the nipple on a 26" wheel.

Imagine what my 20" wheels looked like! I had the new wheel built with cross-two lacing, which is
less extreme.

Guy
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Ambrose Nankivell said:

My LightSPIN has a notice saying not to exceed 30mph for any significant length of time while using
it, presumably because its current limiter may overheat in those conditions.

More likelt because the tyre will catch fire where the dynamo is slipping :-P

Guy
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Just zis Guy said:

Ambrose Nankivell said:

My LightSPIN has a notice saying not to exceed 30mph for any significant length of time while
using it, presumably because its current limiter may overheat in those conditions.

More likelt because the tyre will catch fire where the dynamo is slipping :-P

Now you, just because you've got a hub dynamo doesn't mean that all of a sudden you've got the most
efficient one. No.

I keep my dynamo very well adjusted and it doesn't slip at all.

In my dreams.

Actually, I need to get hold of a new roller cap.

A

My SON makes some noise once per revolution. After one year of use and about 7000 km. It still
works though.

_nospam (Markku Poysti) said:

My SON makes some noise once per revolution. After one year of use and about 7000 km. It still
works though.

What sort of noise? A click or a grumbly noise? Interested.

Guy
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Markku Poysti said:

My SON makes some noise once per revolution. After one year of use and about 7000 km. It still
works though.

You can find some hints on: www.M-Gineering.nl/sonrepag.htm
--
Marten

Quoted message said:

Quoted message said:

My SON makes some noise once per revolution. After one year of use and about 7000 km. It still
works though.

What sort of noise? A click or a grumbly noise? Interested.

Grumbly rather than click. There are about 5 "pulses", always in the same place during one
revolution. The sound disappears if rim rotates very slowly. I often ride in crappy winter weather,
so salt water rust is possible.

Quoted message said:

There are about 5 "pulses", always in the same place during one revolution. The sound disappears if
rim rotates very slowly.

I think this is just resonance, magnets moving the rim as much as bearings allow. If i put some load
on the bearing, sound disapperas.