The Stack Overflow podcast is back! Listen to an interview with our new CEO.
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 ...


9

The main things to look for when purchasing new lights: How bright are the lights? Can you see them for a few feet, a block, half a mile, etc? What is the angle of visibility of the light? It does you no good if you can only see the light from one single point - you want to be sure your light can be seen from a wide range of angles, especially for your rear ...


9

I don't believe these are "better" or "worse" than other lights, rather they are a supplement to other lighting systems. I think the inventors' claims about forward and rear illumination are somewhat questionable as it won't compare to a real head/taillight of similar cost. However, I think they would provide some improvements in side and off-angle ...


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

The Bicycles Stack Exchange Blog now has the most comprehensive bike taillight review on the internet (to our knowledge): Review of the Best Bicycle Tail Lights in 2012 In total I reviewed fifteen different tail lights. The Cygolite Hotshot performed best in the most categories, but there are several other lights which did quite well. If you're looking for ...


8

OK, so: I called Queensland Transport, who put me through to main roads I then called main roads back (since the first call got disconnected). They told me to call my local main roads office, as their central number doesn't answer questions about compliance. I called the local main roads office. The inspector there told me this was an issue of legislation ...


8

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 ...


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 ...


7

Yes, with easy to spot 'caveats'... On 'Critical Mass' bike rides there are all kinds of imaginative lighting setups that give individual riders individuality. We like creativity in cycling and how everyone is different. Undoubtedly these lights are cool and would be fab on a Critical Mass ride. Therefore, for that reason 'yes'. Caveats... LED lights are ...


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

Peter White has done a lot of testing of dynamo headlights and has even put together comparisons of luminance. I have the Schmidt Edelux and love it.


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 ...


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

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 ...


4

Sorry no idea what the el wire looks like. As a driver the best features especially in town are flashing LEDs front and rear, reflective ankle bands (these work from any angle) and relflectors attached to the bike wheels. If you have never driven, do remember that just because you can see the car does not mean the car driver can see you. Car drivers are ...


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.


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

Reading the link and interpetting it in the strictest sense I would say no. My reasoning is that the law states "a reflector" that is clearly visible. It does not say a reflective material that is clearly visible. My other thought is that since reflective tape is cheaper and easier to install, if bike manufacturers could get away with reflective tape they ...


3

Reasonable cost could mean a problem depending on your budget, because a good LED light for dynamo-hubs should not be cheap. My suggestions, based on what I've seen (at night, during some randonneur events) are: From Busch & Müller, the IXON models. Their light is obscenely strong, reaching 100m+ with a good cutoff, thus without annoying other riders ...


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

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 ...


Only top voted, non community-wiki answers of a minimum length are eligible