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Dynamo's & Lights

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Don Whybrow

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Jun 18, 2007, 6:23:41 PM6/18/07
to
I know that there was a discussion on this topic a couple of weeks ago,
but 1) I was a bit busy at work at the time and 2) I don't keep old news
around so anything said has dropped off my machine [1].

Back in May I built up a wheel on a DH-3R40-QR. I have a B&M D'Lumotec
Topal Plus for the front and a B&M Seculite Plus for the rear. The hub
came with a switch that mounts to the top of the fork crown and the
front light attaches to the top of the fork crown. The fitting
instructions for the light state that all the yards of wire should be
used, but this is a bit excessive for the distance that needs to be
covered, so I cut it to a shorter length.

As a result of point 1) above I was commuting after dark, usually on
city streets devoid of traffic or life apart from the late drunks
rolling home. It was during this time that I noticed that after a while
the light output from the main bulb would cut off and I would only be
left with the stand light. I soon discovered that if I stopped the bike,
even briefly, the light would work again for a while ... and so the
process would repeat depending on how concerned I was about having a
bright front light and any intervening traffic lights. I think I recall
reading that this light had a feature that would turn itself off to
protect it in the event of an overload, but I could be wrong.

I have no idea how much difference the length of wire I removed makes
electrically, but I was not under the impression that wire had a high
resistance.

My question to the panel is this. How should I get the thing working
properly?


[1] Yes, I know Google exists.

--
Don Whybrow

Sequi Bonum Non Time

A child of five could understand this! Fetch me a child of five.

Martin Dann

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Jun 18, 2007, 6:44:19 PM6/18/07
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Don Whybrow wrote:

> I have no idea how much difference the length of wire I removed makes
> electrically, but I was not under the impression that wire had a high
> resistance.
>
> My question to the panel is this. How should I get the thing working
> properly?

The length of wire should not make any difference.
They probably don't want you to cut the wire if it has
connectors on the end that you have to reattach or
something like that.
The wiring should have a resistance far lower than the
bulb/LEDs.


I am guessing that you have a loose connection somewhere.
I found when I was testing mine with a loose connection,
it would cut out, and not cut back in until I stopped.

If I were you I would test all connections/wires etc with
a DVM with it all in place before takeing anything apart.

Martin.

Sam Salt

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Jun 19, 2007, 2:39:18 AM6/19/07
to

I have a D Lumotec Oval Senso Plus ( similar instructions ).

It says:-

" Use of this duplex cable incorporated in the headlamp is a
precondition for trouble free operation.It must not be removed ( cut off
completely ).Shortening the cable to the required size is acceptable."

So it seems if you have just shortened the cable then that is not your
problem.The LBS shortened my cable and we have no similar problems.

Sam Salt

M-gineering

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Jun 19, 2007, 3:23:01 AM6/19/07
to
Don Whybrow wrote:
> I know that there was a discussion on this topic a couple of weeks ago,
> but 1) I was a bit busy at work at the time and 2) I don't keep old news
> around so anything said has dropped off my machine [1].
>
> Back in May I built up a wheel on a DH-3R40-QR. I have a B&M D'Lumotec
> Topal Plus for the front and a B&M Seculite Plus for the rear. The hub
> came with a switch
[bingo] ^^^^^^ [/bingo]


that mounts to the top of the fork crown and the
> front light attaches to the top of the fork crown. The fitting
> instructions for the light state that all the yards of wire should be
> used, but this is a bit excessive for the distance that needs to be
> covered, so I cut it to a shorter length.
>
> As a result of point 1) above I was commuting after dark, usually on
> city streets devoid of traffic or life apart from the late drunks
> rolling home. It was during this time that I noticed that after a while
> the light output from the main bulb would cut off and I would only be
> left with the stand light. I soon discovered that if I stopped the bike,
> even briefly, the light would work again for a while ... and so the
> process would repeat depending on how concerned I was about having a
> bright front light and any intervening traffic lights. I think I recall
> reading that this light had a feature that would turn itself off to
> protect it in the event of an overload, but I could be wrong.
>
> I have no idea how much difference the length of wire I removed makes
> electrically, but I was not under the impression that wire had a high
> resistance.
>
> My question to the panel is this. How should I get the thing working
> properly?
>
>
> [1] Yes, I know Google exists.
>


Shimano switches are full of useless electronics which switch of the
lights when the voltage exceeds a certain limit, ie when you're speeding
downhill in the dark.

Replace it with a switch which isn't designed by a committee
--
/Marten

info(apestaartje)m-gineering(punt)nl

Paul Boyd

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Jun 19, 2007, 5:07:10 AM6/19/07
to
M-gineering said the following on 19/06/2007 08:23:

> Shimano switches are full of useless electronics which switch of the
> lights when the voltage exceeds a certain limit, ie when you're speeding
> downhill in the dark.

Yes - I threw away my Shimano switch for much the same reason. Also
because it was impossible to switch on whilst wearing gloves, and the
light sensor part was useless hence the need to use the switch.

--
Paul Boyd
http://www.paul-boyd.co.uk/

Don Whybrow

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Jun 19, 2007, 1:11:50 PM6/19/07
to

Any suggestions for an alternative switch? I don't particularly want to
leave the lights on permanently. I am not too fussed about the light sensor.


--
Don Whybrow

Sequi Bonum Non Time

My veal cutlet tried to beat the shit out of my cup of coffee...
the coffee just wasn't strong enough to defend himself. (Tom
Waits)

Paul Boyd

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Jun 19, 2007, 1:23:39 PM6/19/07
to
On 19/06/2007 18:11, Don Whybrow said,

> Any suggestions for an alternative switch? I don't particularly want to
> leave the lights on permanently. I am not too fussed about the light
> sensor.

Unfortunately not because I got an oval Lumotec thingy with a built-in
switch and sensor. My final straw with the Shimano switch coincided
with me breaking my B&M light, so I killed two birds with one stone.

What might be worth a try is to mount a toggle switch into a little
plastic potting box, running some wires across it and bonding some sort
of handlebar clamp in the open top of the box with resin. Not elegant,
but it should work. By 'potting box', I mean something like the little
cube box at http://www.maplin.co.uk/Search.aspx?criteria=FD96E&DOY=19m6

Jon has moved !

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Jun 19, 2007, 2:14:17 PM6/19/07
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On 19 Jun, 00:23, Don Whybrow <d...@fwhybrow.wanadoo.co.uk> wrote:
> My question to the panel is this. How should I get the thing working
> properly?

I recently bought the D'Lumotec Oval Senso Plus (All-singing... all-
dancing... well, it has a switch and a sensor)

When the wheel was revolving at low speeds (Shimano NX-70) it would
flicker a very bright light. As the speed increased, the output would
decrease in a similar manner to yours.

Over the course of the last week, this behaviour alternated between
bouts of not working at all, until finally when I returned to the shop
I had bought it from it appeared to have died completely. In the
process, the sensor also appeared to have failed (covering it did not
make the light come on!).

The shop has replaced it and the defective unit is being returned to
B&M for investigation.

Best of luck with yours.

Jon

P.S. Hi guys!

Bob Johnstone

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Jun 19, 2007, 3:36:25 PM6/19/07
to
Jon has moved ! wrote:
> Over the course of the last week, this behaviour alternated between
> bouts of not working at all, until finally when I returned to the shop
> I had bought it from it appeared to have died completely. In the
> process, the sensor also appeared to have failed (covering it did not
> make the light come on!).

My experience with a B&M D'Lumotec topal DIWA plus has been pretty poor.
I bought one last autumn. The stand light didn't work very well and
after a few months the main lamp started to fail. The replacement lamp
arrived faulty - the lamp was always on, irrespective of the position of
the switch. The second replacement lamp was of the wrong type (not a
DIWA - not B&M's fault, but the supplier's) so I sent that back in
April. I'm currently waiting for the third replacement and it seems that
B&M is currently unable to supply one.

As I have written before, when B&M's lamps work, they are excellent.
Unfortunately I'm currently wondering whether they have over-stretched
themselves.

Bob

Jon has moved !

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Jun 19, 2007, 3:44:08 PM6/19/07
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On 19 Jun, 21:36, Bob Johnstone <bob.johnst...@physics.org> wrote:
> My experience with a B&M D'Lumotec topal DIWA plus has been pretty poor.
> I bought one last autumn. The stand light didn't work very well and
> after a few months the main lamp started to fail. The replacement lamp
> arrived faulty - the lamp was always on, irrespective of the position of
> the switch. The second replacement lamp was of the wrong type (not a
> DIWA - not B&M's fault, but the supplier's) so I sent that back in
> April. I'm currently waiting for the third replacement and it seems that
> B&M is currently unable to supply one.
>
> As I have written before, when B&M's lamps work, they are excellent.
> Unfortunately I'm currently wondering whether they have over-stretched
> themselves.

There were known issues with a certain batch of this light. Peter
White cycles were encouraging owners to test them to extremes in order
to remove the faulty ones from the system. That was a fault with a
circuit board working loose which actually only affected attached
second lamps, but I do wonder if a similar mechanism isn't at fault
here.

Assuming this one continues to work, then it certainly pays off.
Brighter at lower speeds and no need to carry a spare lamp... ever.

Jon

Danny Colyer

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Jun 19, 2007, 4:02:54 PM6/19/07
to
Jon has moved ! wrote:
> Assuming this one continues to work, then it certainly pays off.
> Brighter at lower speeds and no need to carry a spare lamp... ever.

Unless you forget to disconnect the dynamo before removing the front
wheel and end up yanking the connector off the end of the wire :-/

--
Danny Colyer <URL:http://www.colyer.plus.com/danny/>
Reply address is valid, but that on my website is checked more often
"Daddy, put that down. Daddy, put that down. Daddy, put that down.
Daddy, why did you put that down?" - Charlie Colyer, age 2

Simon Brooke

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Jun 19, 2007, 4:00:43 PM6/19/07
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in message <1182276857....@q75g2000hsh.googlegroups.com>, Jon has
moved ! ('j...@restlesslemon.co.uk') wrote:

> P.S. Hi guys!

Hi Jon! How the devil are you? Still in France? As you see, we've just done
the 7/24 again...

--
si...@jasmine.org.uk (Simon Brooke) http://www.jasmine.org.uk/~simon/
; gif ye hes forget our auld plane Scottis quhilk your mother lerit you,
; in tymes cuming I sall wryte to you my mind in Latin, for I am nocht
; acquyntit with your Southeron
;; Letter frae Ninian Winyet tae John Knox datit 27t October 1563

Jon has moved !

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Jun 19, 2007, 4:32:33 PM6/19/07
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On 19 Jun, 22:02, Danny Colyer <danny_col...@hotmail.com> wrote:
> Unless you forget to disconnect the dynamo before removing the front
> wheel and end up yanking the connector off the end of the wire :-/

Sounds like the bitter voice of experience. As long as the end that
fails is at the dynamo, the laziness which prevented me from cutting
the cable short means that I can afford to make that mistake several
times.

Jon

Danny Colyer

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Jun 19, 2007, 5:24:19 PM6/19/07
to
Jon has moved ! wrote:
>Danny Colyer <danny_col...@hotmail.com> wrote:
>>Unless you forget to disconnect the dynamo before removing the front
>>wheel and end up yanking the connector off the end of the wire :-/
>
> Sounds like the bitter voice of experience.

Quite. I've done it twice now, fortunately I've been able to attach a
new terminal without having to shorten the cable.

> As long as the end that
> fails is at the dynamo, the laziness which prevented me from cutting
> the cable short means that I can afford to make that mistake several
> times.

There's a lot to be said for laziness :-)

I bought the bike with the dynamo ready fitted and the cable routed
through the frame. There's enough cable inside the frame to allow the
boom to be extended fully and then removed, so I've got spare to play
with as long as I'm not worried about being able to remove the boom
afterwards.

mt9...@hotmail.com

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Jun 20, 2007, 7:25:45 AM6/20/07
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On Jun 19, 6:11 pm, Don Whybrow <d...@fwhybrow.wanadoo.co.uk> wrote:
> Paul Boyd wrote:
> > M-gineering said the following on 19/06/2007 08:23:
>
> >> Shimano switches are full of useless electronics which switch of the
> >> lights when the voltage exceeds a certain limit, ie when you're
> >> speeding downhill in the dark.
>
> > Yes - I threw away my Shimano switch for much the same reason. Also
> > because it was impossible to switch on whilst wearing gloves, and the
> > light sensor part was useless hence the need to use the switch.
>
> Any suggestions for an alternative switch? I don't particularly want to
> leave the lights on permanently. I am not too fussed about the light sensor.

after three swap outs of my sw-nx30 (which was doing exactly as yours
was) SJSC sent me a sw-nx10 (handlebar mounted, no light sensor, glove
friendly) by mistake. I ended up fitting it and have had no more
problems. Dunno what your chances of finding one NOS are though.

best wishes
james

Message has been deleted

Jon has moved !

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Jun 24, 2007, 4:10:11 PM6/24/07
to
On 19 Jun, 22:00, Simon Brooke <s...@jasmine.org.uk> wrote:
> Hi Jon! How the devil are you? Still in France? As you see, we've just done
> the 7/24 again...

Not so bad. Still in Paris. You have mail (assuming I haven't been
identified as spam!)

Jon

Bob Johnstone

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Jul 23, 2007, 1:49:36 PM7/23/07
to
Bob Johnstone wrote:
> I'm currently waiting for the third replacement and it seems that
> B&M is currently unable to supply one.

The replacement has now arrived and seems to be working fine. I wonder
whether the guarantee lasts a year from now, or a year from last autumn...

Bob

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