Excellent GCN primer on bike lights

Jeremy McCreary

Bought it anyway
Region
USA
City
Carlsbad, CA
GCN just dropped an excellent video primer on bike lights:


Note the emphasis on checking local laws regarding flashing lights and headlight beam patterns. Blinding other road users endangers everyone involved, including you.

Having just removed my rear fender and its built-in tail light, I happen to be in the market for a replacement. Based on the video, now looking for one with brake light functionality and a secondary downward-pointing beam, like this Magicshine SEEMEE 300/400:


Anyone have experience with this tail light?

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Won't be easy to mount with my big saddle bag in the way, but worth a try.
 
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The Magicshine lights are generally well thought of. One pet peeve: I expect there to be a "clip" option so you can attach it to a pannier or trunk bag.

A lot of bike shops will often have very inexpensive blinkies (like less than $10) that have good mounting options and work well enough if you ride at night infrequently. A good example are the Planet Bike Blinky 3. You can also go even cheaper, like if you have an Ace Hardware nearby they have a decent LED flasher for about $2.

Blinking rear lights are awesome at night because an overtaking vehicle will notice it from an extreme distance and they can usually do a decent job of estimating how far away you are. If blinkies are legal where you ride you really ought to have one. The fancier and more expensive ones usually have an irregular blink which is even harder for a driver to ignore and automagically adjust the brightness between daytime and nighttime riding to make sure you can be seen.

I have experimented and even a very inexpensive blinky is visible from a half mile away, even in poor weather.

I am torn on rechargeable rear lights, because if you use them infrequently AAA lithium batteries will last forever and you needn't worry about remembering to charge the little light you use so infrequently.

Speaking of which, a few mornings ago I had to make an early more departure from here in the predawn murk. After grabbing a coffee I saw, just out of the corner of my eye, the reflectors of a bicycle with no other lights go past me before I turned onto the highway. From behind he was completely invisible. Sure enough, about a half-mile later he was ass over teacup in the left turn lane when he got t-boned. Fortunately he was not injured and even the bike appeared okay. I stopped to tell him he was 100 percent invisible and that he needed some damned bike lights before he killed himself.

Usually I am very hesitant to blame cyclists who get hit, but damn.
 
Jeremy, that Magicshine SEEMEE 300 rear light technology is really cool! I watched review and promo videos. It looks legit! no personal experience with it. It is fairly new. I think the 300 lumens is bright enough based on my experience with lights from 20-350.

As you pointed out the mounting is limited on your seatpost because of the type of rear bag you are using (size and mounting)…but it could work, snug against the bottom of the bag. I really like the downward projection feature. The last rear light I purchased, a Knog Cobber Reflex, also illuminates the ground because of the lens shape @250lumens. But it only has half of the battery capacity of the Magicshine Seemee 300, and is more expensive. I picked it up after riding with a friend who had a similar Knog light. So, I think the Seemee light is a good value.
 
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the problem with magishine they dont have the ANT+ version in us stores. so they come direct from china not super slow. I have the 300 ANT+ and the EVO 1700 UT DI2 & ANT all connected to my Karoo 2. they work really well. I tested the eco on high at home and got about 3 hours run time. commented to the computer on flash mode its full bright get about 8 to 10 hours. I just set up reminders to charge them. but the computer will tell you too. I wanted the automation as I would forget otherwise. thats the advantage of having e bikes with built in lights.
 
Whoa, that downward projection is a pretty neat party trick -- nice halo around the ass-end of the bike. I want to see that in person!

I added a Lezyne StVZO w/ brake function fender mount to my commute bike. It was inexplicably half the price of the Magicshine at my local shop, but it is also far lower lumens. 300 is brighter than many headlights!

Anyhow, the Lezyne shared shelf space with it's sibling, a non-fender mount version. I run mine in combo with a traditional B+M reflector style Toplight mounted to the rear rack. They both burn steady, no flash, which I prefer at night. During twilight or other daytime periods of non-visibility I can set my helmet and/or pedals to blinky mode.

In concept I like the idea of two steady burning tail lights. It conjures up recollections of my Army days using blackout drive, where individual small lamps in the lead vehicle's taillight would resolve as one red, two red, or four red elements depending how far or near I was from it as the driver of the trailing truck.

The taillight I just installed on the new cargo bike is a B+M Dart Brex, similar is size to Busch's other Toplights, but with a reflector in the center, LEDs on either side, and also side marker lights. The Brex tag indicates it has a deceleration-sensing brake light function, with a flashing brakelight for seriously hard stops.

I've been so happy with my B+M IQ-X headlight on the commute rig that I ordered the same for the cargo bike. BTW, too late for me, but if anybody in the SF area wants this light, there's currently a seller on Facebook Marketplace in Oakland with a new one for $60. Unlike most of the other Busch + Müller headlights, this once can be mounted "upside down" i.e. underneath a front rack, because the round light body rotates independently inside the clamp.

Here's a video of the B+M Dart:
 
The Magicshine lights are generally well thought of. One pet peeve: I expect there to be a "clip" option so you can attach it to a pannier or trunk bag.

Yeah, a clip would be ideal for me. Current setup:

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Using this $50, 400 lumen Lezyne Zecto LED tail light for now. The clip is perfect, and the light itself and its 6 or so solid and flashing modes are fine.

But the mode button is very fiddly, battery life is poor, it takes many hours to charge, and there's no brake light functionality.

The Magicshine 300 costs the same.
 
That was one of a very few GCN programmes I was unable to praise or even finish watching. While the GCN cyclists are able riders with tons of experience in cycling, I perceive them as ignorant in bike lighting as most of the rest.
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Digression: One of the GCN guys owns and rides a cargo e-bike. Once, he made a programme how great cargo e-bikes were. It turned out the man -- who is otherwise obsessed with drivetrains, chain cleaning, lubing or waxing -- hadn't even touched his cargo e-bike drivetrain for 2 years and then just replaced it totally. Here's a GCN presenter in the field he's unfamiliar with for you.
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Not only I have been riding e-bikes for over seven years, all year long, day or night, road and off-road. I'm in a WhatsApp group of a hundred experienced gravel cyclists, who discuss bike lighting almost everyday. Compared to those, the GCN guys feel a bunch of amateurs who've heard of the bike lighting for the first time in their lives and only because they got the Magicshine sponsorship.

Magicshine is a recent hype, first of all because it is heavily advertised. The second reason is it is an ANT+ system that can be controlled by drop handlebar "blips": there are not many lights that could be controlled by a drop handlebar rider by the extra buttons. Otherwise, rechargeable battery LED tail lights charged via USB (USB-C recently) and even with the inertial STOP indicator have been with us for years.

There are so many myths around the bike lights, and especially tail lights. One of them is a tail-light should be extremely bright so the rider could be seen. Another is the tail light should blink to draw drivers' attention.

StVZO in paranoidally safe (when it comes to bikes) Germany mandates that:

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While the law of Poland does not forbid flashing lights, an experienced rider in Poland uses the flashing tail light only during daytime, and switches it to steady light at night. Riders of night group gravel rides switch their tail lights off (including Varia), only with the riders declaring riding in the rear having the tail light on.

The truth is brutal: a flashing tail light disturbs the night vision of anyone in the rear, is it a cyclist or a driver.

Then, there come powerful tail lights of, say, 400 lm. Anyone driving in the rear would be blinded, making it dangerous to the cyclist to be overtaken by the approaching car.

Our WA group has this advice:
Turn your tail light on at night and leave the bike alone or under supervision. Walk away as far as possible then turn back and have a look. From what distance can you still see your e-bike?
You could be surprised. Especially when you have got blinded yourself by your powerful tail-light.

Come on. The Lezyne tail light of Vado SL 1 had 11 lm and I have never complained not to be seen. Now, I use an old Lezyne KTV with 75 lm max and use it in the low steady light setting. My big Vado with Supernova M99 45 km/h (an automotive grade e-bike rear light) emits just 9 candelas in normal mode and as much as 50 cd with the STOP indicator. As candelas are not lumens, I estimate that light emitted by the rear Supernova could be just 100 lumens.

I may sound harsh. Yes, I may. Please do the night vision test as described above to make sure you can understand what the driver behind you would see at night.
 
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Quite a rant there, @Stefan Mikes .

During the DAY, my 400 lumen Lezyne tail light flashes at full brightness for long-distance DAYTIME visibility in accordance with California law. It blinds no one during the DAY.

By comparison, the DAYTIME visibility of the Lezyne fender light I removed was marginal at best.

On my rare night rides, I switch the 400 lumen Lezyne to its lowest solid mode. It blinds no one at night.
 
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Adding on to that, I would just point out that you'll notice with lighted aerial antennas, they'll often have strobing white lights during daylight hours that switch to reduced intensity steady-burning reds at night (depending on height -- others will pulse, or more accurately "throb," but not strobe). Flashing lights can be more difficult to track spatially, so while they may get a driver's (or pilot's) attention sooner from a distance, the flashing can be a liability in accurately judging distance when they're in closer proximity, where it counts.

I know there's a lot of rider debate around this, fueled more by personal preference and perception than anything scientifically based. I fall into the steady-burning camp when it's dark, and that includes my pedals and helmet.

A really cool example of this is the flashing red lights on wind farms -- definitely notable because they flash in unison. Attention catching from a distance, but this goal in this case is not to "thread the needle" but instead "stay far away." The opposite would be steady-burning approach lights to a runway, which are used to gauge distance and maintain spatial orientation. Any flashing lead-in lights are used as attention getters from further out, not for close-in adjustments.

 
Have you ever done a daytime visibility test of your 400 lm, Jeremy?
Note: My 400 lm Lezyne was burning my eyes in its lowest steady setting at night. I'm glad I lost it.
 
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