Power To Go: The SON Dynamo Hub

SON DynamoFor a constant source of power on the road and bike lights that never run out of charge, the SON Dynamo hub should be at the top of your bicycle wish list.

We’ve been testing our SON hubs (with Supernova E3 Pro front lights) for about a year. That amounts to some 5,000km of riding. So far, we’re more than pleased. Our love of the SON hub can be summed up in two main points:

1. Power On Demand – You can now run bike lights and charge your mobile phones, GPS systems and other small gadgets, purely through the power of your legs. It is wonderfully freeing to know that you don’t have to worry about batteries any more.

2. Reliable – These hubs are known to be almost worry-free. They come with a 5 year guarantee and should easily see you through a long bike tour. So far, we haven’t had any issues at all to report.

Any disadvantages?

Nothing is perfect. Here are some potential downsides to consider. They’re not dealbreakers for us but you should be aware of them.

1. The Price – We paid €175 per hub. If you want to charge gadgets such as a mobile phone you’ll also need a separate adaptor. Ours is a prototype from Oddbikes (we’ve been told that the full production version will be on the market in March 2012 for about €85). Solutions currently on the market such as the E-Werk, PedalPower and ReeCharge cost about €100.

2. The Weight – Some people note that the hub is a bit heavy (580g) and generates extra resistance. We think the weight and drag is negligible when compared to the overall load of a heavy touring bike – not to mention all the extra batteries and chargers you’d be carrying around if you didn’t have the hub to provide power!

3. Not Field Serviceable – The SON hub is not meant to be repaired in the field. In the unlikely event that you do have problems with it, you’ll have to send it back to a dealer or the factory for repair.

How are we going to navigate this?A SON dynamo hub paired with a Supernova E3 Pro light.

What might go wrong?

We asked Marten Gerritsen, a dealer for SON hubs in the Netherlands, for some opinions on SON hubs and their reliability. He outlined the two most likely ‘worst-case’ scenarios as:

  • Electrical failure – This won’t stop you but will be annoying. Trying to ‘adjust the bearings’ is the main cause of this. A bad solder connection can also happen and to fix this you need special tools.
  • Bearing trouble – This usually happens because water got in the hub. The hub isn’t waterproof and shouldn’t be submerged, for example by crossing floods that are axle deep. Also do not grease the quick release as this blocks the vent hole. Bearing trouble starts as play at the rim, but if you ignore it eventually the bearing cage will collapse and leave you stranded. If you see rust water stains around the axle and detect a lot of play at the rim you’re living on borrowed time

Marten added that he’d never seen problems with broken flanges or with broken or bent axles.

In terms of preventative maintenance, he recommended checking the hub when the rim is replaced. Any play in the hub or irregular noises would be a sign that you should send the hub back to be rebuilt. The cost for this is around €50.

Marten added:

SON hubs come with a five year guarantee, based on experience. As far as the hub is concerned, a bike tour isn’t as bad as occasional use with long periods for corrosion in between. On a typical touring bike, chances are that a Rohloff hub will give trouble before the SON.

Another dealer, Peter White Cycles, says the hub is:

…designed to give at least 50,000 kilometers of trouble free riding between servicing…

That’s more than enough for most world bike tours. Bad luck can always happen but in general we’d be comfortable taking this hub on a long tour. And from the comments on our Facebook group, it seems a few other bike tourists love the SON hub as much as we do!