Author Topic: Repeatedly faulty B&M light  (Read 7461 times)

Re: Repeatedly faulty B&M light
« Reply #50 on: 28 January, 2022, 01:58:28 pm »
I don't find it a problem to be honest. It's way easier to operate with winter gloves on than that stupid twist knob on the cyo. It is the best dyno light I've used by a country mile. I spin wheel with hand, and switch on, no bother. Appreciate that on a recumbent it poses a problem.

Kim

  • Timelord
    • Fediverse
Re: Repeatedly faulty B&M light
« Reply #51 on: 28 January, 2022, 02:05:15 pm »
The Cyo used to switch itself on and off automagically, thobut, so you only needed to touch the switch if you wanted to force it on for bad weather in daylight.  While I agree that the twist knob ergonomics aren't particularly glove-friendly, the knob-moving-a-slide-switch-and-exposing-a-light-sensor design seems to have been eminently reliable, and storing the desired operation state mechanically has obvious advantages.

The rot set in when the StVZO rules started requiring daylight-running lights, and B&M decided to use the light sensor for marginally beneficial reconfiguration of the beam.  Suddenly the recumbent/Brompton friendliness of automatic lighting was defeated.

Cudzoziemiec

  • Ride adventurously and stop for a brew.
Re: Repeatedly faulty B&M light
« Reply #52 on: 28 January, 2022, 02:12:54 pm »
The switching on automagically thing as reported by OD is a fault in one of mine too. I just ignore it and never turn it off. If I was worried about the minuscule power drain from my thighs of Hoy, I'd do some training so I actually had thighs of Hoy. I am, obviously, thankful that the fault is turning itself on not off.

The not being to turn it on except when moving is a different, and far more common, problem. I don't think they're related: one's some sort of loose connection somewhere, the other's shoddy capacitors.
Riding a concrete path through the nebulous and chaotic future.

Oscar's dad

  • aka Septimus Fitzwilliam Beauregard Partridge
Re: Repeatedly faulty B&M light
« Reply #53 on: 28 January, 2022, 02:20:40 pm »
The switching on automagically thing as reported by OD is a fault in one of mine too. I just ignore it and never turn it off...

I ought not to be that bothered.  But it just pisses me off that it is no longer working correctly.

Re: Repeatedly faulty B&M light
« Reply #54 on: 28 January, 2022, 02:25:23 pm »
The Cyo used to switch itself on and off automagically, thobut, so you only needed to touch the switch if you wanted to force it on for bad weather in daylight.

And you can still do that with the Cyo premium. You can have the switch in 3 positions.

Off
Come on in poor light / darkness - main LED
Day light running LEDs  , and switch to main LED once it gets dark / dull enough

This is the one I have on my recumbent, 80 lux rating I think, and cost £45 which I think was good value.

Kim

  • Timelord
    • Fediverse
Re: Repeatedly faulty B&M light
« Reply #55 on: 28 January, 2022, 02:37:55 pm »
Really?  I have a Cyo T Premium on my Brompton, and the modes are:

- Off.
- Sensor selected between 'main beam full brightness + be-seen LEDs dim[1]' and 'main beam dim, be-seen LEDs at full brightness'
- Permanently in 'main beam dim, be-seen LEDs at full brightness' mode.

There's no setting that uses the sensor to turn the light off completely, like the older Cyos.  It's also notable that it draws more power in daylight-running mode than with the main beam on full.

It's an excellent value light.  Not quite as wide a beam as the IQ-X, but reliable and about half the price.  I reckon it's the most bang-for-buck.


[1] The change in brightness of the LEDs is barely perceptible in real-world conditions.  You can see it indoors with a bench power supply if you toggle between the modes a few times.

BFC

  • ACME Wheelwright and Bike Fettler
Re: Repeatedly faulty B&M light
« Reply #56 on: 28 January, 2022, 10:14:03 pm »
B&M lights seem to use volatile memory to remember (or forget!) their last state. Whilst the Lithium battery (IQ U) or supercapacitors (most others with software switching) keep the memory alive they are great.
Once the backup voltage drops they forget their last state and go into default (safe) state and turn on just in case as soon as they "wake up", then whilst riding at low speed the backup device never regenerates unless hitting decent speeds for a reasonable distance without interruptions (worse if running a rear light as well).
If you can get the backup to regenerate they will remember again, but it will not regenerate if the lamp/standlight is drawing more than the input from the dynamo can support for your actual ride speed and static time.
Turning the light off and riding for a while can fix some of them unless the backup is failing or defective - knackered Li battery, bad spring contacts or dry joints on supercaps... I have had all three failure modes on my B&M lights.
Adding other parasitic systems (charging devices) makes the regeneration problems worse.

Oscar's dad

  • aka Septimus Fitzwilliam Beauregard Partridge
Re: Repeatedly faulty B&M light
« Reply #57 on: 29 January, 2022, 04:54:27 pm »
My IQ-X seems to have fixed itself as per BFC's description above.  I'm pleased.

BFC

  • ACME Wheelwright and Bike Fettler
Re: Repeatedly faulty B&M light
« Reply #58 on: 29 January, 2022, 07:02:46 pm »
My IQ-X seems to have fixed itself as per BFC's description above.  I'm pleased.
Ride faster or learn to work within the limits of the dynamo output at your speed (group rides can become a problem though!), Fred, BJ and Dakotas lighting systems will behave differently!

If you understand the way these lights have been programmed, it gives you a chance!
For "slow" riders or anyone stuck in traffic expect these lights to drop into "safe" mode at some time.

With lighting systems - rider confidence (and a backup plan or two) is essential.

Oscar's dad

  • aka Septimus Fitzwilliam Beauregard Partridge
Re: Repeatedly faulty B&M light
« Reply #59 on: 30 January, 2022, 08:18:02 am »
I don't actually know why my IQ-X started to misbehave.  I've had them for years and never had a problem.  Ho hum, one of the mysteries of life I guess.