Chris Nadovich's 2009 Transamerica Bike Tour.

Contact Me

The Schmidt Nabendynamo and SuperNova E3

A mediocre bike rider can sustain a mechanical energy production rate of 100 watts for an hour or more; a good bike rider can sustain 200 watts; racers sustain 400, 500 or even more watts. The Schmidt Dynamo front hub or SON (Schmidt's Original Nabendynamo) diverts just 3 of those many watts, converting them to electrical energy.

The SON is nothing like those tire-driven dynamos you may have seen grinding away the tire sidewall of some Schwinn. It's totally encased in the front hub. Made by Wilfried Schmidt Maschinenbau in Tübingen, Germany, this masterpiece of engineering is quiet and reliable, and designed to give at least 50,000 kilometers of trouble free riding between servicings. The hub can power six volt headlights, including the Supernova E3.

I purchased a built-up front wheel and Supernova E3 from Peter White Cycles. Let me say, before I go any further, that Peter White is a great shop to buy from. The wheel was solidly built, and I received a complete kit of everything I needed roughly on the date I expected to receive it. I highly recommend them to anyone. Good bicycle outfitter.

I also have no complaints about the Schmidt hub. What could anyone complain about. This thing is just about as perfect a machine as anyone could possibly want. It's totally silent, the finish is flawless, and the mechanical drag of this brushless, permanent magnet, AC generator is practically unmeasurable. You can feel some magnetic detents if you turn the axle directly by hand, but on a built-up wheel (especially with a massive Schwalbe tire) the detents are almost undetectable.

The E3, on the other hand, isn't quite as perfect. Good, mind you, just not perfect. My main complaint is the mount. I selected the standard multimount for fork crown mounting and, indeed, this mount just barely works. I have V-brakes and I can either snake the brake cable through the hole in the mount arm or try to clear the cable over top. Neither arrangement seems "right". I expect I'll eventually make a replacement bracket that works better.

Another problem with the bracket is that the hinge screws are threaded into the aluminum with only about 3 threads in metal. The first time I tightened them to what I thought could withstand the vibration of a 1200K brevet, I stripped the threads completely out. Fortunately, McMaster-Carr saved the day again, with longer screws, spring washers, and nuts with nylon inserts.

I don't have any experience riding at night with this setup. I need to do that ASAP. I'd also like to measure some electrical data. Charging my cell phone during the day seems like an achievable goal.

   permalink