Author Topic: NEW - Busch & Muller Luxos Front Light  (Read 102707 times)

Re: NEW - Busch & Muller Luxos Front Light
« Reply #200 on: 25 April, 2013, 11:50:33 pm »
Comments to a picture above: wire loop down and up, prevents water main stream running straight to the lamp's connector, and wiring it through mount, should keep it tight connected.

Yes, I was going to say that it looked like they were just advising to wire it in with a kind of "drip loop" to prevent water running down the wire and straight in to the connectors.
"Yes please" said Squirrel "biscuits are our favourite things."

Re: NEW - Busch & Muller Luxos Front Light
« Reply #201 on: 26 April, 2013, 01:14:21 am »
Dear, rogerzilla, don't forget it's just a small accumulator (cache) and it may be constantly charging and discharging on long rides with electronics gadgets on (GPS, smartphone or camera, AA/AAA charger). I'm not a professional electronics specialist, but I won't hope to be it alive more than 2-3 years.

How long the battery will last depends of course on a lot of different things, but probably mainly the amount of charge cycles. But as I understand it, it is strictly a battery cache, not an extra battery pack. So its main function, when i comes to charging, is to deliver a continuous amount of power at a steady voltage. So I don't think any connected USB device is allowed to discharge it fully.

If the connected USB device, on average, can be charged by the dynamo's output, the cache battery will only discharge very little. Lets assume a 20%* discharge per trip when charging a smartphone. With 2 trips per day, 250 days per year, the battery will then have had what amounts to 500 full discharges after 5 years before it goes below specification. Even then, it will probably function for quite a while after its 500 charge cycles, it will just provide "buffer" power for a shorter time slots when charging a USB device.

* a 20% discharge is of course simply a guess, maybe its is more, maybe it is less. But remember, the above scenario assumes daily USB charging most days of the year. I think it is safe to assume that the discharge pattern is way less when it comes to daily use (standlight and even flood light). My point here is mainly to illustrate that you can't necessarily compare a cache-battery's lifetime to that of a normal battery pack in eg. a Smartphone.



BTW, BUMM's answer to my question about numerous product returns and reports coming into forums and feedback about water ingress, failing battery and strange light behaviour was: "Please do not put too much stock in internet hysteria. If you use our product as we described, there won't be any malfunction :-)".

I think it is general very good advice not to be overly concerned with any random product trashing on the Internet. I own and have owned superb products that some have given extremely unfavourably  reviews of, sometimes because their expectations where different, sometimes because they didn't have the technical knowledge to use the product.
There is also extreme selection bias in most product reviews that gives a really distorted perspective.


Some other experiences and by other users in comments under it too.

This is unlikely to be a problem with the Luxos. Let me explain; there will never be any guarantee that any random USB product can be charged by a "dumb/dedicated" charger like a hub dynamo, especially when using any random USB cable. The main reason for this is that the original USB specification didn't allow for enough current to charge Smartphones, so Smartphone producers made up their own different standards for USB charging.

Gradually the original USB specification got changed to allow for high current charging, so things are less insane now. But there are still potential major problems. The present USB spec allows for two different ways of charging; intelligent charging (CDP) that also allows data transfer, and dedicated charging (DCP). The connected USB device can discern between what kind of charger it is connected to, because USB-cables connected to dedicated chargers have shorted the D+ and D- pins. (this is fairytale simplification, reality is much more complicated with many different deviating "standards").

So if you use a standard USB cable in a dedicated charger like a hub dynamo, the connected device can get very confused. Per standard the device will accept 100 mA and will then try to communicate with the charger, trying to negotiate a higher load. Since it gets no answer, it assumes there is an error are therefore likely to drop the connection after a while. I think this what happened to the guy in the linked story.

So always use a dedicated charger USB cable when connected to dedicated charger like a hub dynamo, not a random standard USB cable. Sometimes it work using a standard USB cable, though it sometimes mean an artificial limit on how much current that can be drawn, but don't count on it.

Also note that there are many different dedicated charging cables and standards, some may adhere to the simple shorted D+ D- pins standard, others don't or have extra inserted resistors etc. www.dx.com usually have a wide selection of dedicated USB charging cables for those obscure variations that exist out there.

Finally, it may sometimes be necessary to change the configuration of the connected device. Some devices will eg. turn off the screen when connected to a USB cable with power, because they assume that this means they are connected to a pc, or that they aren't meant to be used while charging. Such behaviour can sometimes be changed in the firmware /software setup.

--
Regards

Re: NEW - Busch & Muller Luxos Front Light
« Reply #202 on: 26 April, 2013, 12:40:26 pm »
Thanks, Interested, for a detailed explanation. BUMM should hire you to add some more leaflets in English :) That will save them a lot money and returns on fake problems. Anyway, I'll hope they will make a replaceable battery in future :thumbsup:

BTW, regards to the picture above about USB section illustration. There is an USB sign on connector shown on the top in light's manual (or web PDF), but, I guess, it should be opposite way, to connect it properly. Some users may fail to connect due a wrong drawing :) So they just changed a drawing to a good one.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #203 on: 26 April, 2013, 01:16:47 pm »
After reading all the comments I am going to stick to my English Lumicycle LED 3Si (52 battery) I have had it approx 3 years riding through our lovely wet summers and all other weathers, it provides more than enough light output, takes any weather that is thrown at it and the battery lasts for so long it is amazing. I love the idea of a fit and forget light like the B&M but from all the posts on here it aint going to let you forget it
The problem with the world is that fools and fanatics are always so sure of themselves, and wiser men so full of doubt.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #204 on: 26 April, 2013, 01:34:43 pm »
Yes, Quint, I think, that looping wire down and up, can't solve a problem completely, but only confirms a design flaw – bad wire/contact/lamp box sealing from water. Despite looping down, it may be affected by a strong side rain too. It's not about mudguards on, they – must have on touring bike, especially with those "hot" lamps, that need venting from the bottom :)

Re: NEW - Busch & Muller Luxos Front Light
« Reply #205 on: 26 April, 2013, 05:17:52 pm »
Yes, Quint, I think, that looping wire down and up, can't solve a problem completely, but only confirms a design flaw – bad wire/contact/lamp box sealing from water. Despite looping down, it may be affected by a strong side rain too. It's not about mudguards on, they – must have on touring bike, especially with those "hot" lamps, that need venting from the bottom :)

Is there any reports at all that mentions that water can ingress the lamp when the plug and wire is correctly connected? I have a really hard time believing that the connector isn't IP64 certified at least. The reports I have seen have all lacked basic information like whether the Luxos was charging while it rained etc.

I think it is much more likely that any water ingress came through handlebar plug, perhaps because it was unprotected or a device was plugged in.  This is a problem with all hub dynamo chargers, since standard USB ports aren't waterproof. The solution to hub charging in the rain is to place the USB handlebar plug in the bar bag.
--
Regards

Re: NEW - Busch & Muller Luxos Front Light
« Reply #206 on: 26 April, 2013, 08:46:21 pm »
Yes, Quint, I think, that looping wire down and up, can't solve a problem completely, but only confirms a design flaw – bad wire/contact/lamp box sealing from water. Despite looping down, it may be affected by a strong side rain too. It's not about mudguards on, they – must have on touring bike, especially with those "hot" lamps, that need venting from the bottom :)

Is there any reports at all that mentions that water can ingress the lamp when the plug and wire is correctly connected? I have a really hard time believing that the connector isn't IP64 certified at least. The reports I have seen have all lacked basic information like whether the Luxos was charging while it rained etc.

I think it is much more likely that any water ingress came through handlebar plug, perhaps because it was unprotected or a device was plugged in.  This is a problem with all hub dynamo chargers, since standard USB ports aren't waterproof. The solution to hub charging in the rain is to place the USB handlebar plug in the bar bag.

        With the greatest respect this is designed for a bicycle/tricycle (etc) so should not need any private modification not even moving it to a bar bag to protect it, it should be able to stand a deluge, fine/heavy snow and so on, with B&Ms resources surely it is not beyond them to create something to their normally very high standards.
         Personally I would resort to good old vaseline but do not see why I should have to on what is/should be a quality bit of kit.
The problem with the world is that fools and fanatics are always so sure of themselves, and wiser men so full of doubt.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #207 on: 26 April, 2013, 08:51:21 pm »
Yes, it's hard to be justice, when You don't know exact details, but in my point of view:
– There are some reports about problems in the rain. It may be, but it's unlikely, that all of them used USB port in the rain. It's instructed not to do this in manual (OK, who reads it? :-)
– This new leaflet shows how to place a wire and something about water ingress (I don't speak German too), but it's not about that USB port on a "button" at all.

I see three ways water to get in:
1. Not properly closed USB port or used in the rain (put it under plastic (may BUMM include it in kit?) or in waterproof top tube/handlebar bags (looping wires down too), if you do so). It may be done.
2. Use mudguards, to prevent water getting from the bottom (don't mount it's top facing down too, don't use water jet to wash it :-) It may be done to.
3. Connector plug not properly connected to the lamp (use new BUMM advise – loop down and keep it tight). Well, it may be hard to achieve, unless you check it all time to be tight or "glue" it somehow – vibration does it's job. BUMM should place this connector under the lamp in a cave shaped cut (or face it down), water should run down, not up or along it then. That's why I call it design flaw. Maybe it's a good idea to close this jack in rain at all and put this wire to a safe bag (solves both: 1 and 3).

Let's wait for more "happy" users reports and more details :)

Re: NEW - Busch & Muller Luxos Front Light
« Reply #208 on: 26 April, 2013, 09:09:27 pm »
You have to have the bar cable connected, otherwise water will get in.

But on this set of instructions there is a clear message about water getting in via the bar switch/usb and recommends not using it in the wet, and if you must, then cover the switch unit with `plastic` ::-)

Two contradicting translations! 

I understood the instructions that if you don't have the bar cable plugged in, you must make sure the rubber flap is closed properly, and also to ensure that you don't charge things when it's raining and make sure the flap on the handlebar switch is closed when it is raining.

Those instructions deal with different cases. The first concern the handlebar button and how to make sure that no water gets into the light through the hole for its jack, e.g. by closing it properly when the jack isn't plugged in.

The English translation of the part about the USB socket left out one sentence. Before the recommendation not to charge in the rain the German version warns that mobile devices generally don't have a waterproof USB socket and that's the reason not to use the USB interface in the rain.

I'm about 15km from the B+M HQ at the moment and could visit them but am afraid not even German engineers will work tomorrow :-)

Re: NEW - Busch & Muller Luxos Front Light
« Reply #209 on: 26 April, 2013, 09:26:38 pm »

Paragraph 5 (Die Rücklicht...)
I will just paraphrase this: "The rear light monitor only function correctly when the correct polarity connection is observed. If the polarity is wrong, the rear light monitor LED may be light up, even if the rear light is turned off, because of the cache-battery.

To clarify, the two situations where the rear light monitor may fail are independent. When the polarity is wrong it may not work and I read that to mean it could fail in either way.
If the rear light has standlight functionality the monitor may detect a current and show the light as on even if it's switched off when the capacitor is charging.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #210 on: 26 April, 2013, 11:57:03 pm »

        With the greatest respect this is designed for a bicycle/tricycle (etc) so should not need any private modification not even moving it to a bar bag to protect it, it should be able to stand a deluge, fine/heavy snow and so on, with B&Ms resources surely it is not beyond them to create something to their normally very high standards.
         Personally I would resort to good old vaseline but do not see why I should have to on what is/should be a quality bit of kit.

I think you misunderstand me. Let us assume that the B&M Luxos is watertight when correctly mounted and and all cables and plug covers are plugged in. We are in agreement here, that in this situation, the Luxos ought to be watertight. But I have yet to see a single report of water ingress where the reporter explicitly said that the Luxos had its cable securely installed and the handlebar button plugged with the cover.

Where you are wrong is to assume the impossible, namely that a plugged in standard USB plug can be made watertight enough, like IP64 (http://en.wikipedia.org/wiki/IP_Code)
AFAIK, it can't be done with the present USB standards. There will be water ingress if it rains hard enough with any USB connection, so even if B&M magically made their USB connection waterproof, the connected device would take in water, leading to potential shorts and corrosion. Notice that all so called waterproof Smartphones only remain waterproof when the USB port is covered up.

That was my point, no matter what charging device one uses, it should be physically protected from rain by eg. a bar bag when charging USB devices, or else you risk water ingress at either the charger or the connected device.


(edit: corrected a potential misunderstanding)
--
Regards

Re: NEW - Busch & Muller Luxos Front Light
« Reply #211 on: 27 April, 2013, 12:54:32 am »
Yes, it's hard to be justice, when You don't know exact details, but in my point of view:
– There are some reports about problems in the rain. It may be, but it's unlikely, that all of them used USB port in the rain. It's instructed not to do this in manual (OK, who reads it? :-)

If they left the USB port on the handlebar button open, they would experience problems too.
The quality of the reports I have seen until now have been really low, with very few details about what actually happened. This is probably because that the people reporting didn't have much technical insight into the subject. So personally I think that "user errors" are a much more likely, than the USB port plug isn't waterproof.



– This new leaflet shows how to place a wire and something about water ingress (I don't speak German too), but it's not about that USB port on a "button" at all.

I have translated /paraphrased that leaflet previous in this thread. The section you are thinking of, recommend running the wire through the lamp bracket. The point is that the connection to the lamp is placed asymmetrical to the right side. If the user isn't careful when running the wire, it is possible that it may snag the lamp while the handlebar is turned to the left, this may put so much tension in the wire that the it may become unplugged. One should always install such wires so that there as little tension and bending as possible. The B&M's recommendation is one such solution, but zip-ties and careful installation may yield the same results even though the wire runs differently.
The mentioning of water ingress just concerns the obvious fact, that when the wire is unplugged at the lamp, it is possible that water may ingress.


[snip]
3. Connector plug not properly connected to the lamp (use new BUMM advise – loop down and keep it tight). Well, it may be hard to achieve, unless you check it all time to be tight or "glue" it somehow – vibration does it's job. BUMM should place this connector under the lamp in a cave shaped cut (or face it down), water should run down, not up or along it then. That's why I call it design flaw. Maybe it's a good idea to close this jack in rain at all and put this wire to safe bag (solves both: 1 and 3).

I don't think water running slowly along a wire when the bike is stopped should have any chance of entering a properly made waterproof plug. If the bike is moving at speed, the water on the wire will be pressed backwards, even if it loops downwards. Such slow drips are nothing compared to a large rain drop hitting the connection directly at 50 km/h. It is possible to make a plug that can resist even a jet wash of water when installed correctly, whether this is the case with the B&M Luxos U, I don't know, but I haven't seen any indication of water ingress at the lamp plug when the wire was correctly plugged in.

(edited: replaced "right" with "left")
--
Regards

Re: NEW - Busch & Muller Luxos Front Light
« Reply #212 on: 27 April, 2013, 11:15:12 am »
As (I believe) someone else mentioned here, why not make the USB connection with a sealed cable exiting the light to be connected when/if needed, the problem I would worry about is ingress into the light and this would solve it.
      I must admit to deciding not to buy this as a fit and forget supplement to my Lumicycle (can't have to much light)
The problem with the world is that fools and fanatics are always so sure of themselves, and wiser men so full of doubt.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #213 on: 27 April, 2013, 01:27:27 pm »
As (I believe) someone else mentioned here, why not make the USB connection with a sealed cable exiting the light to be connected when/if needed, the problem I would worry about is ingress into the light and this would solve it.
      I must admit to deciding not to buy this as a fit and forget supplement to my Lumicycle (can't have to much light)

No, an extra cable wouldn't solve the fundamental problem about standard USB ports and plugs not being waterproof. You would still have to charge the device inside a eg. bar bag or similar when it rained.
And there would still be a socket that needed a cover when unused, but instead of being on the handlebar, it would be on the lamp.

Besides that, a separate cable would introduce several new problems. The cable would have to use a proprietary waterproof connection where it is attached to the lamp, so either it would necessary to supply several different cables, each with a different USB plug like Micro USB, Mini B etc (a la E-Werks), or it could be terminated in a female USB plug so one could attach the USB charging cable that could connect with the device. Having several different proprietary cables is a really bad solution when attached to a stationary lamp, since they would invariable always be too short or too long. It works with the E-Werks because the unit itself can be moved to compensate for cable length.

So a separate cable would actually mean two cables, and if you forget either, you can't charge your devices. Besides, such loose cables tend to disappear when not in use. And if you wish to leave the proprietary attached to the lamp when not in use, you would have to plug it with a cover too, just like the present solution.

All in all I would say that the present B&M design of the Luxos is quite smart and a very good compromise.
The charging socket is always available (no  proprietary cable to forget, no expensive proprietary cables that may disappear)
The USB plug is facing rearwards something that really helps against water ingress: The speed of the water is the major factor when it comes to make a connection waterproof. If you descend at 50 km/h in the rain, the rain drops will hit with +50 km/h. so by shielding the port by making it face rearwards is a smart move.
Much simpler cable routing and fewer cables and connections.

No other solution I can think of will reduce the amount of sockets that needs to be covered when not in use.
No other solution I can think of will remove the need for physically protecting the connected USB device from the rain by eg. placing it in a bar bag.

It also look quite easy to remove the handlebar USB port since it is attached by a rubber band, and I quite can't see a pressing need for having the button available when charging in the rain.

--
Regards

Kim

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Re: NEW - Busch & Muller Luxos Front Light
« Reply #214 on: 27 April, 2013, 03:35:16 pm »
I can imagine adequate waterproofing of an arbitrary USB plug connection by completely enclosing it in a case, with a flexible rubber seal (possibly more than one) that closes around the cable.  That is however going to be awkward, bulky and prone to fatigue failure.

And still doesn't make the connection at the other end waterproof.


Having the button available is presumably desirable to put the light into boost mode for technical surfaces and fast descents.  That's going to be just as useful in the rain as in the dry (possibly more so).

Re: NEW - Busch & Muller Luxos Front Light
« Reply #215 on: 27 April, 2013, 05:20:53 pm »
I can imagine adequate waterproofing of an arbitrary USB plug connection by completely enclosing it in a case, with a flexible rubber seal (possibly more than one) that closes around the cable.  That is however going to be awkward, bulky and prone to fatigue failure.

And still doesn't make the connection at the other end waterproof.

Sure, you could eg. place some kind outer casing on the cable that could be screwed into the lamp, making it very waterproof, but that again would for all practical purposes make it at proprietary cable, so why use a USB plug at all as connection, since you would have all the drawbacks of using a properiatary cable, but only one of the advantages (waterproof at one end).

I think any contraption that could be clamped around a standard USB cable would be utterly impractical, and as you point out, prone to failure. But I also think it couldn't be made waterproof enough. A rubber boot pressing against a surface isn't much defence against water ingress, especially when wind resistance puts a lot a pressure on.


Having the button available is presumably desirable to put the light into boost mode for technical surfaces and fast descents.  That's going to be just as useful in the rain as in the dry (possibly more so).

The B&M Luxos U only charge with 100 mA if the lights are on, so why even bother charging when doing fast descents at night when it rains. No matter what brand of hub dynamo and charger, there will be inherent limitations like this. They can't deliver both maximum light output and charge a power hungry USB device at the same time.

There will always be design compromises, but I think for the vast majority of user cases, the B&M Luxos U solution is the best. Sure one could design it with a edge user case like; "the need to use floodlight while doing fast descents in the rain, and at the same time needing to charge a device". But as I tried to explain earlier, such an optimization (like a separate charging cable) would introduce other problems, and be much more bothersome to use in the much more common user cases.

--
Regards

Kim

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Re: NEW - Busch & Muller Luxos Front Light
« Reply #216 on: 27 April, 2013, 05:29:33 pm »
Having the button available is presumably desirable to put the light into boost mode for technical surfaces and fast descents.  That's going to be just as useful in the rain as in the dry (possibly more so).

The B&M Luxos U only charge with 100 mA if the lights are on, so why even bother charging when doing fast descents at night when it rains. No matter what brand of hub dynamo and charger, there will be inherent limitations like this. They can't deliver both maximum light output and charge a power hungry USB device at the same time.

Who said anything about charging?  I was giving a reason for wanting the button accessible in the rain...


Agreed about charging while running the lights.  I can see it being useful for keeping an eTrex ticking over on an Audax, but that's about it.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #217 on: 27 April, 2013, 05:34:43 pm »
Having the button available is presumably desirable to put the light into boost mode for technical surfaces and fast descents.  That's going to be just as useful in the rain as in the dry (possibly more so).

The B&M Luxos U only charge with 100 mA if the lights are on, so why even bother charging when doing fast descents at night when it rains. No matter what brand of hub dynamo and charger, there will be inherent limitations like this. They can't deliver both maximum light output and charge a power hungry USB device at the same time.

Who said anything about charging?  I was giving a reason for wanting the button accessible in the rain...

I thought that was implied, because there is no need to place the handlebar button in a bar bag unless the USB cover is off while it charge a device. The handlebar button ought to be waterproof enough to used in even extreme rain while descending as long as the cover is on the USB socket.
--
Regards

Re: NEW - Busch & Muller Luxos Front Light
« Reply #218 on: 27 April, 2013, 07:43:24 pm »
I give up  :P   I (as stated before) will stick to my no water ingress problem, no run time problem (unless artic or Scottish winter (same thing)  )  Lumicycle, made in England, Led 3Si light, as for charging I shall visit every damnded pub along the way with my charger (no change there then  ;D)
The problem with the world is that fools and fanatics are always so sure of themselves, and wiser men so full of doubt.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #219 on: 19 May, 2013, 02:24:52 pm »
From comments: http://aushiker.com/busch-muller-lumotec-iq2/

Quote from: David L. May 19, 2013 at 12:33 PM
I also had my Luxos U fail after using it in the first significant rain. 12 hours off and on rain during a 400km Audax Brevet in Japan. I was using fenders, and did NOT open up the USB charger port during the entire event …

Some more info:
http://translate.google.com/translate?sl=de&tl=en&prev=_t&ie=UTF-8&eotf=1&u=http://www.teltarif.de/lumotec-iq2-luxos-u-test-usb-handy-laden/news/50760.htm
http://translate.google.com/translate?sl=de&tl=en&prev=_t&ie=UTF-8&eotf=1&u=http://www.rad-forum.de/showflat/Number/900170/page/7

321up

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Re: NEW - Busch & Muller Luxos Front Light
« Reply #220 on: 23 May, 2013, 04:41:59 pm »
 :thumbsup:

Fitted this week, so far so good.  Using with Schmidtt Son 28 (new 2012 model).  I noticed the electronics (?) occasionally make a whine noise at low speed (~7 mph), seems to be at about the point where it switches from battery to dynamo power.  I guess it's working hard to boost the voltage until it's got sufficient speed.  Has anyone else noticed this?  Just used on one ride so far.  Seems to charge my Samsung S3 ok, fairly well with the headlight off, and the phone even indicated that the battery had charged a bit even whilst I had the headlight on (no rear light connected yet).  The USB charging continues for a short while from the internal battery after stopping, but not as long as I had expected.  Need a longer ride to test it properly...

Re: NEW - Busch & Muller Luxos Front Light
« Reply #221 on: 18 June, 2013, 10:56:09 am »
Safety notice: Got both Luxos U and Toplight Line Plus brake lights? Read this.
http://www.joe-bike.com/2013/06/12/safety-notice-got-both-luxos-u-and-toplight-line-plus-brake-lights-read-this/

Re: NEW - Busch & Muller Luxos Front Light
« Reply #222 on: 18 June, 2013, 12:12:00 pm »
Safety notice: Got both Luxos U and Toplight Line Plus brake lights? Read this.
http://www.joe-bike.com/2013/06/12/safety-notice-got-both-luxos-u-and-toplight-line-plus-brake-lights-read-this/


That is my setup, bugger  - and I see Peter White has updated his page with a compatibility chart for tail lights that suggests no grounded tail lights and definitely not the Toplight Line Plus.


Mine has been problem free over 300-600km audax events this year so I will have to decide whether to fret or not...

Kim

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Re: NEW - Busch & Muller Luxos Front Light
« Reply #223 on: 18 June, 2013, 12:19:44 pm »
Interesting.

It's probably worth noting that with a bit of wiring-fu (or perhaps nylon fixings), it's possible to make some grounded rear lights float wrt the frame.  Disconnect the wiring from the mounting bolt, make a hole for the cable and make a proper insulated connection internally.  I did this on one of my lights as a side-effect of having to drill new mounting holes to make it fit the rack.

It's not clear whether the problem with grounded rear lights is simply that the tally doesn't operate correctly, or something more serious.

Re: NEW - Busch & Muller Luxos Front Light
« Reply #224 on: 02 August, 2013, 11:17:43 am »
BUMM's answers to my questions:

1. Q: Incompatible with some rear lights?
A: The problem of compatibility between Luxos U and Toplight Brake Tec rear light was due to a particular component in a small quantity of Brake Tec lights. It had nothing to do with the functionality of the Luxos U itself. The Toplight brake tec has since been released in a revised version where this problem no longer occurs. (It only occurred in a very small number anyway).

2. Q: Water ingress into plug problem?
A: Although this problem only occurred in very few Luxos U headlights our ambition is to have the best quality possible, so the new version of Luxos U has no plug, but the cable enters the light directly through a sealing ring, making water intake at this point impossible.