Review: Biologic Joule Dynamo Hub and Trelock Lights

Lighting is a crucial element for bicycle safety. While there are plenty of battery-powered lights on the market, they only last for so long before the batteries need to be replaced or recharged—plus you have to remember to bring the light with you! Dynamo hubs offer endless electricity, powered by your pedals. The only trade-off is that the small amount of rolling resistance you get while generating that electricity can be, well, a drag. A new hub from Biologic has a way to get around all that.


The Biologic Joule HG hub is the first of its kind, in that a rotating switch mechanism disengages the dynamo and allows the hub to spin without resistance. Though it can’t be switched while riding, turning the dial while stopped is a simple matter.

But here’s the thing: while the ability to run smooth and drag-free in the daylight is a nice option, the Joule hub is so efficient when engaged, I never felt the need to switch it off. I kept the hub generator engaged and the lights on day or night. Can’t have too much of a good thing, right?

The hub, as I tested it, is part of a complete front wheel offered by commuting and touring specialists Cantitoe Road. It’s laced to a DT Swiss TK 540 rim with DT Swiss spokes. While the hub is disc brake-compatible, the rim has a machined braking surface, so it will work with any kind of bike. Weight weenies and racers might want to look elsewhere, as this is a stout, solid wheel for touring or commuting.


Dynamo-powered lights are far more common in Europe than in the U.S., and most manufacturers of dynamo lights hail from there, including Trelock from Germany.

The LS 875 model is the top of the line, with a three-way on/off/auto switch that can detect if it is dark and turn itself on. While that feature seems nifty, I left it on all the time—set it and forget it, right? While it pumps out a respectable 40 Lux, I found it still wasn’t quite bright enough to light my way on pitch-dark country roads.

I also tested the LS 820 rear light, which has a pretty amazing feature—it senses when the rider is slowing by the reduced power output and flashes brighter, indicating “slowing or stopping” to riders or motorists behind.

All the parts needed to attach the lights to any dynamo hub are included, and everything wired up without a hitch. In fact, it took me longer to route the rear light cable nice and neat than it did to wire up the rest of the system. The whole thing is pretty much plug-and-play.

If you’re interested in giving dynamo-powered lighting a try, Cantitoe Road has resources for choosing the system that’s right for you, including package deals. The full kit consisting of front wheel and lights, as pictured here, retails for $650.




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