Author Topic: Repeatedly faulty B&M light  (Read 1471 times)

Kim

  • Timelord
Re: Repeatedly faulty B&M light
« Reply #25 on: November 27, 2019, 12:46:57 pm »
- Ripping the plug off when you get a front puncture while tired.

I reckon the Shimano/SP lego-brick style connectors have an advantage in this respect, as (as long as they're aligned vertically) they'll disconnect well before ripping the cable off.  And if it does get ripped off you can re-make the connection at the roadside without any special tools (you just need a pokey thing to release the two halves of the connector).
Careful, Kim. Your sarcasm's showing...

Kim

  • Timelord
Re: Repeatedly faulty B&M light
« Reply #26 on: November 27, 2019, 12:48:01 pm »
Legally if you have a dynamo without standlight, you're supposed to only stop on the left, which makes right turns a bit difficult. I don't suppose anybody actually paid any attention to that rule even back in the pre-standlight days. But legality isn't my concern, it's that we're no longer in the pre-standlight days. You'd nowadays have to deliberately search for dynamo lighting without standlight. Why would you do that rather than choose one of the many easily available, brilliant (pun intended) and efficient dynamo systems with standlight?

Quite.

Also, my standlight gets regular use for identification of keys at the end of the ride.
Careful, Kim. Your sarcasm's showing...

Re: Repeatedly faulty B&M light
« Reply #27 on: November 27, 2019, 06:58:36 pm »
My B&M Avy doesn't have a standlight but there is only one right turn on my commute where I ever have to sit and wait, and that's in a right turn-only lane protected by a traffic island.  It does have a big built-in reflector under the lamp.
Never tell me the odds.

Re: Repeatedly faulty B&M light
« Reply #28 on: November 27, 2019, 09:21:37 pm »
….we're no longer in the pre-standlight days. You'd nowadays have to deliberately search for dynamo lighting without standlight. Why would you do that rather than choose one of the many easily available, brilliant (pun intended) and efficient dynamo systems with standlight?

Rear light standlights I think are a good idea and (IME) when they go wrong they don't usually cause the whole light to fail.

  However unless your front standlight meets the requirements of any of the applicable standards, then legally speaking it might as well not be there. In terms of being seen, a feeble glow-worm might seem to  be better than nothing but it may just give you a false sense of confidence.  In terms of actually being seen, if you are in the beam of a car's headlights and have reflectors/reflexite fitted, a typical standlight will hardly register amongst this lot.  So I have my doubts about the true value of such a thing.

  If you have to make a single right turn in a journey you would be as well (or better) off with a simple (and legal) blinky rather than a standlight. Come to think of it I would vote for front standlights to be blinky not steady, as that way they would be more likely to produce a legally compliant amount of light and would probably contribute better towards you being seen.

I also note that lamps with standlights often develop odd behaviours, eg not switching on a low speed unless the capacitor is charged, and decreased levels of brightness at low speeds until the capacitor is well charged.  It is most certainly not the case that such a thing comes without potential drawbacks.

What I don't have any doubts about is that the standlight is the thing that is most likely to go wrong in many front lights.  Look inside a typical light and there is no concession to the fact that the light will see a lot of vibration; both the supercapacitor and the choke are usually mounted in such a way as they will simply fatigue off the board, sooner or later.  I'd far sooner that they spent money on things in the light that make it better and more reliable, not worse and less.

I always carry a backup light of some kind and I use this for thirty seconds whenever I have to navigate from the bike to the back door and/or lock the bike. This means I am always sure that the thing still works, without which it could be nigh-on useless.

Regarding bracket breakage; this is (obviously) more likely to happen if the lamp is heavy. I dunno how much extra the standlight/senso/DRL  gubbins weighs but it is some extra weight rather than none. I've never seen a wire-type  bracket break with a simple, lightweight lamp mounted to it.    You can avoid the lamp housing itself breaking by simply choosing a lamp that isn't too heavy and mounting it on a bracket that will move when it is clouted, rather than a stupid 100% rigid mount. Obviously the lighter the lamp is, the less tight the bracket needs to be, and the less likely any real damage is to occur.  Strategically placed spring washers in the mountings can help with all this.

Regarding wire breakages; I prefer not to use zip ties because they concentrate the bending strain in the wire at one point, and if they are done up tight enough to stop the wire from moving in service, it may not pull through when tugged. I normally use tape instead; if taped correctly the wires don't flex at one point and will pull through if they see a hard tug.  A Brucey top tip is to have a little excess wire doubled up under the tape; this means there is excess for repairs and it also means a hard tug will just cause more wire to miraculously appear rather than lead to a breakage.

  I have always arranged to have wires such that they will pull off the generator rather than break first; e.g. by having connectors that just pull out (I ran for about 25 years with such a setup; it never gave me a moment's worry). In more recent years (with a shimano hub)  I have just used the centre part of a shimano connector; this pulls off the generator quite easily and also allows the thing to be fettled/rewired very easily should this be necessary.  However if the wires are a bit flimsy, you could lose the plug off the end of the wire when the wheel is out I suppose.

On the subject of accidental damage I recently saw a (almost new) hub generator that got mangled into oblivion when a simple bungy cord hook got dropped into the front wheel.  It got dragged round with the wheel and smashed the connector block to pieces.

It is very easy to spend a fortune on lights and still end up with a system that is a bit shit.  However with a bit of thought and application you can have a system which is inherently more reliable and it doesn't have to cost a fortune or be a PITA to live with either.

cheers

Re: Repeatedly faulty B&M light
« Reply #29 on: November 28, 2019, 12:30:10 am »
The lesson I've taken away is that you should probably carry a backup battery light whatever you do, and if you do that you don't need absolute reliability out of your dynamo system, and if you do that you can have whatever components you want and set it up however you want and not have to consider reliability above all else, which is a losing game.

Re: Repeatedly faulty B&M light
« Reply #30 on: November 28, 2019, 05:42:04 am »
The lesson I've taken away is that you should probably carry a backup battery light whatever you do, and if you do that you don't need absolute reliability out of your dynamo system, and if you do that you can have whatever components you want and set it up however you want and not have to consider reliability above all else, which is a losing game.

This

The amount of redundancy varies from area to area. When I rode the Silkroute 1200 I carried a pre-mounted spare dynamo frontlight. And I needed it as the B&M light's bracket wasn't up to Uzbek road conditions.

Re: Repeatedly faulty B&M light
« Reply #31 on: November 28, 2019, 09:09:31 am »
The lesson I've taken away is that you should probably carry a backup battery light whatever you do, and if you do that you don't need absolute reliability out of your dynamo system, and if you do that you can have whatever components you want and set it up however you want and not have to consider reliability above all else, which is a losing game.

anybody with half and ounce of common sense at least carries enough spare lighting that they can fix a puncture if needs be and these of course  double up as emergency lights too.

However I don't think it is an accident that I've been riding around in the dark for decades with various dynamo lighting systems and I have not had cause to use the backup lights as yet.  The likely reason for this is that I have been careful to choose components that are not intrinsically unreliable and I have been careful to install the parts using various commonsense arrangements that greatly reduce the risk of both damage and problems arising from it.

I'd suggest that if you choose intrinsically reliable parts, your emergency lights need be for emergencies only. However if you choose/install  poorly, you had better carry a spare set of lights and be prepared to use them.

cheers

cheers

jiberjaber

  • ... Fancy Pants \o/ ...
  • ACME S&M^2
Re: Repeatedly faulty B&M light
« Reply #32 on: November 28, 2019, 09:50:34 am »
The lesson I've taken away is that you should probably carry a backup battery light whatever you do, and if you do that you don't need absolute reliability out of your dynamo system, and if you do that you can have whatever components you want and set it up however you want and not have to consider reliability above all else, which is a losing game.

anybody with half and ounce of common sense at least carries enough spare lighting that they can fix a puncture if needs be and these of course  double up as emergency lights too.

However I don't think it is an accident that I've been riding around in the dark for decades with various dynamo lighting systems and I have not had cause to use the backup lights as yet.  The likely reason for this is that I have been careful to choose components that are not intrinsically unreliable and I have been careful to install the parts using various commonsense arrangements that greatly reduce the risk of both damage and problems arising from it.

I'd suggest that if you choose intrinsically reliable parts, your emergency lights need be for emergencies only. However if you choose/install  poorly, you had better carry a spare set of lights and be prepared to use them.

cheers

cheers

To add some balance to the thread in terms of reliability I have 27,000km of untroubled running of Luxus-U and 29,000km of IQ-X (of which I have 2 on different bikes).

Like all components there's always some quality control issues and the nature of the internet is such that it's usual to mostly see negative reviews and experiences when searching (not sure when the last time I thread asking how can I take something that is working OK and break it ;D )

Carrying some form of secondary lighting is just common sense though I tend to combine it with at least some usefulness rather than just being dead weight as a spare, so head torch (helps to better see around bends when at speed) and secondary rear battery light (for added rear visibility).  :thumbsup:
Regards,

Joergen

Kim

  • Timelord
Re: Repeatedly faulty B&M light
« Reply #33 on: November 28, 2019, 12:56:11 pm »
On the subject of accidental damage I recently saw a (almost new) hub generator that got mangled into oblivion when a simple bungy cord hook got dropped into the front wheel.  It got dragged round with the wheel and smashed the connector block to pieces.

Damaging the hub seems like a relatively optimal outcome in that scenario.  Nasty things, bungee cords.
Careful, Kim. Your sarcasm's showing...

Cudzoziemiec

  • Dormant but requires tea
Re: Repeatedly faulty B&M light
« Reply #34 on: November 28, 2019, 02:30:13 pm »
On the subject of accidental damage I recently saw a (almost new) hub generator that got mangled into oblivion when a simple bungy cord hook got dropped into the front wheel.  It got dragged round with the wheel and smashed the connector block to pieces.

Damaging the hub seems like a relatively optimal outcome in that scenario.  Nasty things, bungee cords.
Yeah. Remember when they were used as lower fixings on panniers? I got one caught in the wheel while riding and... actually it just pinged out again, but that was a much smaller hook and tiny cord compared to a load-fastening bungee. I've also got a proper bungee caught in a motorcycle wheel once; that ended up with decapitated bungee, but even the weeniest motor puts out a bit more power than my legs.
The unwilling rider and the one who leaves each control in turn without reluctance, with no desire to come back, obviously cannot be making the same journey, even though their brevets are identical.

fd3

Re: Repeatedly faulty B&M light
« Reply #35 on: November 28, 2019, 11:42:55 pm »
I have a ... years old cyo (40lux model) which has been faultless.  The second hand "U" flickers a bit intermittently, I don't like it but it's okay on the recumbent (which I rarely ride at night).  The IQ-X turned itself off three times on the ride home tonight - I would believe that I just can't solder, except that the technicians at work gave it the once-over.
I don't see the point in having a light that requires a backup - yes, I should have something so that I can limp home if need be, but it should be the exception as opposed to the rule.  My experience with the IQ-X is that it will stop working more frequently than my battery lights run out.
[/I could be wrong]