Dynamo power deserves to be more popular, and Shimano's catchily named DH-3N80 dynohub sits at the top of their range and offers performance to match. Okay, it's not quite as smooth as a top-end Schmidt hub but it's not as spendy either.
The DH-3N80 hub is light, well sealed and built to last, using tried-and-tested technology: it shares the labyrinth contact sealing and Borazon treated cup-and-cone bearing races with Dura Ace and XTR components. The 6v/3W dynamo outputs to a push-in wiring port that makes plugging in pretty simple and secure; the hub is earthed through the axle too if you're running an old-school setup like me, meaning you only need one wire for lighting, returning the current via the frame. Remember not to fit ceramic bearings in your headset... The wiring plug is easy to remove and the hub itself uses a quick-release skewer, so it's simple to take the wheel off.
I built my 32-hole hub into a Mavic Open Sport rim and the resulting wheel is sturdy and rolls very well. It'd take a more finely tuned athlete than me to notice the drag from the hub out on the road, although of course there will be a tiny amount. Spin the wheel in the frame with no load to the dynamo and it'll happily freewheel for 20 seconds or so, half that when it's running lights. Mainly I've used the hub for lighting and it's been flawless. I've also tested it with a USB charger - no problems there either.
At 523g it's heavier than Shimano claim (490g) but it's the lightest unit they do. If you're not worried about a small weight penalty then the DH-3N72 is a bit heavier and about £25 cheaper for a similar build spec.
Well made lightweight dynamo hub for your audax bike or posh commuter
road.cc test report
Make and model: Shimano DH-3N80 hub dynamo
Size tested: 32H
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
* Highly efficient, super light weight, premium grade 6 volt 3 watt dynamo front hub with easy to use quick release
* Provides bright illumination for safer night riding without the need and expense of replacing batteries
* Important weight savings are made by using an efficient and light weight aluminium coil structure
* For use with rim brakes
* Labyrinth and contact sealing as used on the premium Dura-Ace and XTR groupsets - low-friction seals and internal grease sleeve effectively shut out water, mud, and dirt without affecting rotational smoothness increasing service life
* Borozon treated cup and cone bearing races - super mirror finish bearing races reduce friction providing smooth and precise bearing rotation
* Push-in wiring harnesses make installation fast and easy
* Double anodized, premium finish forged aluminium hub shell
* Comes with an easy to use quick release skewer
* Average weight 490 grams
The weight's a bit out, but no other arguments...
Very nicely put together
Worked perfectly during testing
Again no problems; haveing had other hubs that use the same sealing I'd be prepared to bet it'll last well
Not as light as they say it is
Not too pricy. The DH-3N72 is probably a better bet for many applications
Tell us how the product performed overall when used for its designed purpose
Tell us what you particularly liked about the product
Consistent and low-drag power
Tell us what you particularly disliked about the product
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
About the tester
Age: 38 Height: 190cm Weight: 98kg
I usually ride: whatever I'm testing... My best bike is: Genesis Equilibrium with SRAM Apex
I've been riding for: 10-20 years I ride: Every day I would class myself as: Experienced
I regularly do the following types of riding: time trialling, cyclo cross, commuting, sportives, general fitness riding, fixed/singlespeed, mtb, Mountain Bike Bog Snorkelling, track
Dave is a founding father of road.cc and responsible for kicking the server when it breaks. In a previous life he was a graphic designer but he's also a three-time Mountain Bike Bog Snorkelling world champion, and remains unbeaten through the bog. Dave rides all sorts of bikes but tends to prefer metal ones. He's getting old is why.