Lights going out suddenly

"Javier Manchón" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Hello to everyone:

I´m having problems with my lights in my early morning commute and I would like to ask for
your advice.

The bike is fitted with a Shimano Dynamo Hub, B&M Lumotech on the front, and Dtoplight on
the rear.

I have been using them for a year without any kind of problem and I am very satisfied with this
set up, but lately things are not the same:

Everything seems to be working OK, when suddenly the light goes out. When this happen I pull out
to the shoulder of the road turn, by hand, the front wheel, the light turns on, and I resume the
commute with the light working until it goes out again.

I have made tests with the two switches I have (the two models of shimano, the older that is
fitted on the handlebar and the new one with photoelectric cell) the problem is the same with both
of them.

I have checked the wiring, and there not seems to be any short-circuit. Both, front and back
lights seems to work perfectly and both go out simultaneously, so the problem seems to be in an
different place.

This only happens when cycling, and after a few miles. If I test the system turning the wheel by
hand or starting from stop the light allways works OK. It doesn´t depend on speed, humidity,
quality of the road or anything I have been able to figure out.

Have any of you had this same kind of problem before?

Intermittent lighting problems? Electrical string problems - connections or wire. I had a similar
problem and rebuilding one of the joints in the lamp fixed it. Nothing apparently wrong with it,
but still...

Since it's both lights, how about the connections between the dynamo and everywhere else? Is the
spade connector dying? Is the wire that goes through the axle ok? Wires can die in unobvious ways
through corrision - I've peeled back the insulation on an otherwise ok wire before to find a pile of
black strands.

cheers, clive

Javier Manchón said:

Hello to everyone:

Quoted message said:

The bike is fitted with a Shimano Dynamo Hub, B&M Lumotech on the front, and Dtoplight on
the rear.

Ooh! ooh! Me too! And I have *precisely* the same problem.

Is the light a round one? If so you need to take it apart every now and then and use a pair of
long-nosed pliers to put the bias back into the flat contact inside the lampholder. This works for a
while and then it gets worse again. Mine deteriorated over - well how about that! - a year, and is
now a complete pain in the bum, so I'll be replacing it with either the Bisy (from tubus.nl) or the
Schmidt E60 which shares the same optics. Both perform better than the Lumotec.

Apparently the oval Lumotec is not as prone to this problem (Google in recent threads for
more info).

--
Guy
===
I wonder if you wouldn't mind piecing out our imperfections with your thoughts; and while you're
about it perhaps you could think when we talk of bicycles, that you see them printing their proud
wheels i' the receiving earth; thanks awfully.

highwaycode.gov.uk09.shtmlOpen ↗ highwaycode.gov.uk09.shtmlOpen ↗

you know? said:

Javier Manchón said:

The bike is fitted with a Shimano Dynamo Hub, B&M Lumotech on the front, [...]

Ooh! ooh! Me too! And I have *precisely* the same problem.

Is the light a round one? [...] Mine deteriorated over - well how about that! - a year, and is now
a complete pain in the bum, so I'll be replacing it with either the Bisy (from tubus.nl) or the
Schmidt E60 which shares the same optics. Both perform better than the Lumotec.

Bother! I wish I'd read this before buying one. Oh well, I'll keep the round Lumotech for now; it's
good enough with a battery backup / secondary, and in a year's time perhaps I'll replace it with
whatever people are recommending then.

At least I now know how to fix it when it goes wrong. Thanks Guy!

--
Andrew Chadwick <Secure beneath the watchful eyes

you know? said:

Javier Manchón said:

Hello to everyone:

Quoted message said:

The bike is fitted with a Shimano Dynamo Hub, B&M Lumotech on the front, and Dtoplight on
the rear.

Ooh! ooh! Me too! And I have *precisely* the same problem.

Is the light a round one? If so you need to take it apart every now and then and use a pair of
long-nosed pliers to put the bias back into the flat contact inside the lampholder. This works for
a while and then it gets worse again. Mine deteriorated over - well how about that! - a year, and
is now a complete pain in the bum, so I'll be replacing it with either the Bisy (from tubus.nl) or
the Schmidt E60 which shares the same optics. Both perform better than the Lumotec.

But the OP said it was happening to both front and rear lights at the same time. I'd go with a
wiring fault.

Quoted message said:

Tim
--
fast and gripping, non pompous, glossy and credible.

Thanks you all for your response.

Yes, the culprit seems to be the front light: Yesterday afternoon I replaced it for the old one I
have (plain 2,4 bulb, no halogen, no standlight, no electronics, no nothing) and this morning I made
all the way without any failure.

Tim, thanks for your advice, but I had a wiring problem some months ago (a "sharp" edge in the rear
pannier caused a slight peeling in the wire that drove me crazy until I discovered it) an rebuilt
the whole wiring with a more robust wire and a more straight path, so I was "sure" that this was
not probably the cause. Way both lights went of bugs me, but I have no explanation about it. Would
the electronincs in the Shimano photoelectric switch, cut off the power in case of failure in any
of the lamps?

Guy thank you very much for your instructions. By the way, the rear cap that covers (I think, there
is no other place for it) the condenser, is it glued to the lamp body? I have been tampering with it
and I have not seen any clear way to dismantle it

Un saludo

Javier

Javier Manchón said:

Hello to everyone:

Everything seems to be working OK, when suddenly the light goes out.

When that happens its usually a sign you are about to be abducted by aliens

Tony

raven-family.comraven-family.comOpen ↗

"The single biggest problem in communication is the illusion that it has taken place" George
Bernard Shaw.

Tony Raven said:

Quoted message said:

Everything seems to be working OK, when suddenly the light goes out.

Quoted message said:

When that happens its usually a sign you are about to be abducted by aliens

Those aliens must have a really wierd view of the human race - the only people they ever seem to
abduct are loonies!

--
Guy
===
I wonder if you wouldn't mind piecing out our imperfections with your thoughts; and while you're
about it perhaps you could think when we talk of bicycles, that you see them printing their proud
wheels i' the receiving earth; thanks awfully.

highwaycode.gov.uk09.shtmlOpen ↗ highwaycode.gov.uk09.shtmlOpen ↗

Tim Hall said:

But the OP said it was happening to both front and rear lights at the same time. I'd go with a
wiring fault.

I think the dynamo electronics cut out if something like that happens - I leave my rear light on
Auto mode because that way it stays on, otherwise mine also goes out when the front lamp does.
That's why it took me a while to work out what the problem was - I suspected the automatic switch
for a long time, but when I bypassed it the problem continued. It's possibly a short in the front
lamp causing the trouble, but either way stopping and restarting fixes it. And yes, it sucks :-)

--
Guy
===
I wonder if you wouldn't mind piecing out our imperfections with your thoughts; and while you're
about it perhaps you could think when we talk of bicycles, that you see them printing their proud
wheels i' the receiving earth; thanks awfully.

highwaycode.gov.uk09.shtmlOpen ↗ highwaycode.gov.uk09.shtmlOpen ↗

Quoted message said:

Those aliens must have a really wierd view of the human race - the only people they ever seem to
abduct are loonies!

loonies? you talking to me? you calling me loony?

I am only a pacific nutty who happens to be pedalling at 6,30am in the middle of the winter dark,
wearing strange (and thermal) gloves, shoe covers and cap, riding a bike that is decorated like a
Christmas tree, with a plastic orange reflective flag sticking out from the side...

If you call this loony... ;-)

"Javier Manchón" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I am only a pacific nutty who happens to be pedalling at 6,30am in the middle of the winter dark,
wearing strange (and thermal) gloves, shoe covers and cap, riding a bike that is decorated like a
Christmas tree, with a plastic orange reflective flag sticking out from the side...

If you call this loony... ;-)

Can you think of any other possible explanation for such behaviour?

No -- thought no.

😉

Hello Guy,

Could you please help me about what exactly to do to, even temporarily, fix the problem?

My excuses, but I have been unable to figure it out from your post.

When I dismantle the Lumotec here is what I got:

The Plastic holder of the mirror, that doesn´t have any business in this.

The cylindrical *main body*. In there, there are the two external connectors (mass and positive)
that are wired, one to the golden spring, that holds the bulb in place (mass) and the other one to
the flat contact in the bottom of the *bulb connector well*(positive)

I take it that when you say *to put the bias back into the flat contact inside the lampholder* The
*flat contact* refers to the same flat contact I´m talking about. (it is the only flat contact I
have found there)

If this is the case, the question is: What I´m exactly to do. I´m sorry but I don´t understand what
you mean with *put the bias back...* (I´m sorry again, this time about my English (and I mean it)
but is the only one I have)

Could you explain it to me as if I were a simpleton (many people thinks this to be the case)

Un saludo

Javier

Javier Manchón said:

I take it that when you say *to put the bias back into the flat contact inside the lampholder* The
*flat contact* refers to the same flat contact I´m talking about. (it is the only flat contact I
have found there)

That's right - you grab the edges of the flat bit with a pair of long nosed pliers and pull it
towards you. It's that simple.

Email me if that desn't work - [email hidden]

--
Guy
===
I wonder if you wouldn't mind piecing out our imperfections with your thoughts; and while you're
about it perhaps you could think when we talk of bicycles, that you see them printing their proud
wheels i' the receiving earth; thanks awfully.

highwaycode.gov.uk09.shtmlOpen ↗ highwaycode.gov.uk09.shtmlOpen ↗