Beating the Heat (Instead of Myself) with a Dynamo Headlight

For people working regular business hours, it’s usually in the Fall and Winter when they need reliable bike headlights.  The sun sets earlier, and daylight saving time kicks in in other parts of the world.

In Tucson, I found myself commuting home after sunset even though it was the middle of the summer.

Some days, around quitting time, I’d dread the 10- to 12-mile commute home in the mid-summer heat pushing 110 degrees. So I’d work late, and not because I’m a dedicated, hard-working employee; because I wanted to wait for the temperature to go down with the sun.

These were some of my favorite commutes in Tucson. I’d have one or another river path mostly to myself under a starry sky. I’d see bats, rabbits and other critters in my headlight. These commutes were serene.

And a small part of that pleasure was the Biologic Joule HG  dynamo hub lent to me by Cantitoe Road along with a  Axa Nano 40 dynamo headlight.

Axa Nano 40 dynamo headlight
Axa Nano 40 Dynamo Headlight.

I’m quite familiar with battery powered bike headlights. In particular, I’m a big fan of USB rechargeable bike lights. This was my first experience with a dynamo-powered bike light.

Even with USB powered lights, I’ve had the occasional dead battery which usually is accompanied by some short-term self loathing.

Idiot! There was a USB port right there on your computer. Right there! All goddamn day long!

That kind of thing.

The peace of mind was definitely a benefit — knowing that I’d have lighting no matter what else I may have forgotten to do that day. In addition to that, not having to worry about depleting batteries or remembering to charge them gave me license to run the headlight at all times — even on my morning commute with plenty of daylight, improving my visibility to drivers of motor vehicles.

The Nano 40 light, with 40 Lux, was not as bright as my regular headlight, a Light and Motion Urban 500, with 500 lumens. Lux? Lumens? Sigh. I don’t know how many Lumens the Axa light has, or how many Lux the Light and Motion light has.

Candela vs. Lumens vs. Lux
Want a better explanation? Google it. Graphic: Cantitoe Road

The Light and Motion light has a pattern more like the light at the top of the diagram. The Axa light has a pattern more like, well, like none of the examples in the diagram.

It looked like this diagram:

Axa 40 beam pattern
Bunny included for scale, but not included with the light.

The Axa light, like Busch & Müller bike headlights, uses fancy reflectors to make sure no light is wasted, and that means the pattern on the ground isn’t necessarily oval or symmetric.

I couldn’t stop seeing the outline of a skull projected in front of me. (Pareidolia strikes again.)

Beam Skull
But maybe that’s just me.

In addition to being the first dynamo light I’ve ever tried, it’s also the first headlight I’ve used that is mounted at the fork crown. There were a couple of bike racks around town that didn’t want to play nice with the headlight in this position. But the light was easy to adjust, without tools, and return it back to its optimum skull-projecting position.

Fork Crown Light and Bike Rack

Because I was using the Montague Boston 8 folding bike, I had to remove the front wheel with the Biologic dynamo hub more often than one would with a non-folding bike. There’s plastic clip that holds the bare wire ends from the light to the contact points on the dynamo.

Axa wire tips and the Biologic Joule HG dynamo hub
Not intended for frequent plugging and unplugging.

Every time I removed the front wheel (say,  to throw the folded bike into the trunk of a car) I’d worry about losing this clip. If I were to be keeping this light and wheel, I would probably glue those wire ends to the outside of that clip.

Biologic Joule HG Dynamo Hub
Biologic Joule HG Dynamo Hub | Photo: Cantitoe Road

A clever feature of the   Biologic Joule HG dynamo hub is that you can turn it off, in contrast to most dynamo hubs which create a little bit of drag even when the lights are not being used. I tried not to worry about this much. But once, and only once, when I was in a big hurry, I dropped the Octagon stem on the Montague bike into a more aero mode, and turned off the dynamo. I bet I got to my destination in 34 minutes instead of 35.

I mostly loved this setup — especially when I had the somewhat obvious realization that it wasn’t the dynamo powering the light, I was powering the light.  That made night commuting even more satisfying.

The Biologic Joule HG Dynamo Hub sells for $200
Cantitoe Road will build you wheel with the Biologic Joule HG Dynamo Hub for $450
The Axa Nano 40 Dynamo Headlight sells for $99.95

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5 thoughts on “Beating the Heat (Instead of Myself) with a Dynamo Headlight”

  1. I-Cycle says:

    Great article!
    I’ve been riding with a dynamohub (shimano) and Trelock headlight for 1,5 year now and wouldn’t go back to battery lights for sure.

  2. Dr. M says:

    This brings back memories! My Royce Union with a generator powering my head & tail lights. Good until I stopped pedaling.
    I’m sure the Dynamo you tested is part of a new breed but I like to run my lights during the day for extra visibility.

    I upgraded to a Cree 3,000 lumen rechargeable headlight from and a Dinotte Lighting Daytime Red.
    Even in broad daylight these lights are crazy bright. Cars slow down and go
    around me now. So cool! I really don’t ride at night but if I need to, this headlight can handle it. Thanks for posting this!

    1. Ted Johnson says:

      I completely forgot to add that broad-daylight benefit. I just updated the piece with this very long sentence.

      In addition to that, not having to worry about depleting batteries or remembering to charge them gave me license to run the headlight at all times — even on my morning commute with plenty of daylight, improving my visibility to drivers of motor vehicles.

  3. Joel says:

    Once again, I lament that I cannot invest in such a fine system knowing that I cannot pack it into my bag at the end of my commute.

    I do run all of my lights on strobe during the day and I wear my full reflector vest whenever I get on my bike.

    The batteries are all rechargeable but I like the idea of breaking free of fuel AND electricity presented here.

    With every month of commuting by bike, I fine tune and reinvest some of my savings to make the commute easier, more enjoyable, and reliable. This item fits into more enjoyable (see your surroundings), safer (lights on at all times), easier (no batteries to charge or change), and reliable (no batteries needed).

    Sigh…, maybe one day my Park-N-Ride will have bicycle lockers so I can add some of these goodies to my ride.

    I need not ask anyone here anymore but what the heck, “Did I tell you that I like to ride my bicycle?”

  4. Nick says:

    The best part of a dynamo setup is no fumbling with batteries and light straps with gloveless hands in sub-freezing temps.

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