19

I'd recommend learning to do arm signals. Arm signals don't run out of batteries, and are plenty visible in most cases. They're certainly bigger than the turn signal lights you could put on a bicycle (which as Moz points out in a comment, makes distinguishing the 2 turn signals a possible issue), and the distance you need to see a bike turning is a lot ...


12

I have actually dramatically improved the cutoff on my 1200 lumen dual LED (just for reference) with a sort of brim made out of aluminium plate. On road I run it on minimum brightness (guessing about 1/4 -- 1/3 power). On pitch dark bike paths I do change the angle a little as well as turning up the brightness. Super-speedy sketch (go inkscape!): The ...


11

Batteries, especially most types of rechargeables don't work well in cold conditions. The chemical reaction that powers the electric voltage does needs some temperature to perform as intended. If you then have a consumer load that requires a bigger amount of power, they tend to drain rather quickly since they cannot set free much energy when cold. You could ...


11

There are two reasons why it might not work: The batteries don't like the cold. Many battery chemistries don't like the cold -- notably alkaline, manganese (heavy-duty), and NiMH/NiCad batteries. To test this hypothesis, put your light (or even just the batteries) in your freezer. If your light gets weaker the colder it gets, this is your problem (...


11

This happens because the power from a hub dynamo (which technically is a magneto, not a true dynamo) is not clean sine-wave AC but consists of short pulses with alternating polarity. At high speeds these pulses follow each other fast enough that a LED can burn continuously with a small capacitor and a filament bulb does not have time to cool down between ...


10

USB rechargeable lights are not typically designed to be run off of USB power continuously, they're only designed to be charged over USB. I run The Bike Light Database, and have tested dozens of different USB rechargeable lights. A few models will run while plugged in, but typically do not charge if turned on, and only run at the lowest output setting. If ...


9

In Germany, all bicycle lights above a certain lumen value have to have a low beam feature, so it's pretty standard here. So, if you do not want to kludge your existing headlight get a german one, e.G. Busch und Mueller Headlights always have a low beam feature, which they especially advertise. Here is their english web page. http://en.bumm.de/


9

I have a helmet mount very similar, and yes its totally possible to dazzle and annoy any other road user, from pedestrians to other cyclists to motorised vehicle drivers. Benefits to a helmet light Its high up above the ground and higher than handlebar lights, so other road users can see it over cars. The beam follows your head, so you can light up the ...


8

You would be entering in a very busy market with no obvious advantages. Let's look at the two types of LEDs that you might use: If you're using inexpensive and low-power 5050 LEDs (15 lumens@350mW; usually ganged in groups), then you could power the lights off button cells (two CR2032s would power one 5050 LED for about 3 hours; 3 x 5050s for one hour) but ...


8

The most important part of a vehicle light is the optics because you want a beam with a precise shape and distribution in order to illuminate the road evenly, without wasting light into the sky or blinding people coming in the other direction. These optics are very difficult and expensive to design. It is easy to make a circular lens which will throw half ...


7

When checking a Dynamo system, there are 3 basic items which need confirmation: Power Supply: Is your dynamo producing power? Checking this requires a multimeter, preferably with alligator clips on the wiring, and to spin the hub. Or there are specific tools, as well. Wiring continuity: Are all connections tight? Are there any breaks/shorts in the circuit? ...


6

Lights that are road-legal in Germany have this cut off. The Trelock LS 950 is a good example.


5

I too had major interference problems between my 700lumen Smartlight (no, not the Garmin one, just a brand called Smart) and VDO M6 wireless computer with all 3 sensors (speed, cadence, HRM) stopping when light was on. I tried wrapping the light in normal, household aluminium foil and hey, it works! Not too pretty but no need to spend time making a bracket ...


5

The problem is the current controller built into the LED bulb has no or ineffective EMC suppression. This is extremely common in cheap equipment from unbrand named suppliers, who save costs by not going though the rigourous CE or FCC testing requirements. They also cut costs by not placing components (usually a small cap is all thats needed), and lay out the ...


5

Thought I should update this just in case anyone's been looking (probably not so much in summer!). I got a good deal on a B&M Cyo plus. This has a switch and standlight. The rear light connection is switched AC. I bought the cheapest standlight equipped rear light I could find with no switch. The front light comes on and off with the switch as you'd ...


5

To give a brand neutral answer: all the big light brands have at least some o-ring mounting styles now, but some of them still offer clip-in brackets as optional parts for the same lights. And there are still some around that come with that type, but it's the kind of brand-specific thing that changes a lot and so is off-topic here. So short answer, find ...


4

As a Revo Lights owner I like them a lot as a second light source. Since the light is lower to the ground they do a better job of lighting up the pavement immediately in front of you. For being seen, they're much more visible than many of the headlights and tail lights I see on other bikes out at night. Especially from the side, when you're at a stop sign ...


4

If your rear light will not come with standlight function, so (in the options I know) the front light with standlight will not "turn it on" at the rear light. Such lamp is AXA Echo 30 Auto Steady. It has cable to connect it to the hub dynamo connector and output for the rear light. But don't get misleaded. This output only transmits current when dynamo is ...


4

Not necessarily blind, but annoy and distract. For oncoming traffic, the best lights are ones mounted below eye level and that limit the upper beam. The easiest way to check for this online is to see if a light is sold by a German mail order store and whether it passes StVZO regulations.


4

The brake detection is based on an accelerometer, and is not a complicated feature. I have had a similar feature on a Chinese front light and it worked ok from what I can see. So that's probably not a key reason to buy a branded light instead. Amazon are often parasitical in these products - AliExpress charges $11 for a similar (same?) thing https://www....


3

Don't attempt user service. The rubber front-piece doesn't give access to the body, the case body is tightly shut, and there is no way in through the power button. All you'll do is ruin the pre-existing water resistance by damaging the seal on the rubber front-piece. Do leave the light indoors in a dry area and allow natural movement of moisture to clear ...


3

A hub dynamo is typically rated at 6V/500mA, and most lights will use all of that. Modern LEDs give you a lot more light from that power, but it's still nowhere near as much as the high powered battery lights you can buy (so if the manufacturers could get more power into the lights they would probably offer it as an option). So the extra power you're ...


3

The motion of the light is what does the work, the colour is less important as long as its bright. A valve light will describe a "flattened corkscrew" through the air and is obviously different to any other vehicle on the road - which means you get perceived by driver's conscious brains not just their subconscious or autonomous brains. These things are ...


3

I suspect you will find 800 lumen to be plenty, even for avoiding debris on unlit roads. For context, I commute in the dark (and often in the rain) along unlit back roads and along our regional trail system which is unlit double track gravel with forest coverage. I often need to avoid fallen branches, rabbits and the odd deer that pops out of the trees at ...


3

Going fast on unlit roads you definitely want a decent light. Personally I find the combination of my 100 lumen dyno headlight plus another 100 lumens on the handlebars to be enough, but I ride relatively slowly and on a manoeuvrable bike. On a faster bike with handling and brakes designed for speed you want more. Perhaps not 2000 lumens - that's off road ...


3

Shimano hub generators have an electrically connected axle (stupid but fact, it comes from the time when bicycle lights were connected unreliably using a single cable closing the circuit using the frame). Even modern rear lights have this electrical frame connection, too (B&M Cyo is clean in that matter). This means your circuit is built of two cables ...


3

Learn to look back while riding straight. That is much more important than making any signal. Also the movement of the head is usually a good indication to the driver behind of what your intentions are.


3

Suggested compromise: Hand signals, but wear reflective material on your arms to make those signals more visible.


3

I would start by pulling the seatpost, fork and the bottom bracket. Use a small mirror similar to a Dentists type to try to see if the wire is attached in the frame or just passes thru. You may then be able to remove it. If possible attach a string to the end of the cable. You can then use the string to pull the repaired light cable back through the frame.


3

Have a friend wear your helmet with the light mounted on it like you planned. Then go to a small residential street at twilight and see for yourself whether it is too bright. Bring a car and try passing each other a few times, both in the twilight and when it gets completely dark. If it blinds you, see if dimming the light or aiming it down helps. If not, ...


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