The Axa HR Traction dynamo is more hi-tec than the Nordlicht, but it it is not as robust. Its benefits are that it has a lighter body, a voltage limiter (dynamos had a reputation for burning out tungsten filament bulbs), and a very neat connector block that allows the connection of up to four stripped wires (two for the front light, and two for direct connection to the back light). It is also cheaper than the Nordlicht. It has a rubber wheel, but I found the dynamo body fouled the spokes, so unlike the Nordlicht above I run this dynamo on the tyre wall (upon which note the dynamo track). The geometry of this bike meant that it didn't fit well on the rear wheel, so it is mounted in the traditional Dutch style, with the wire taken up the front fork to the headlamp, secured in place using zip ties. Note the use of a small piece of butyl rubber (pond liner off-cut) to provide mechanical isolation between the dynamo and the fork. This reduces vibration through the frame, and stops the paint being scratched. This bike has oversized forks, which meant I had to substitute some longer bolts from my junk box. These were slightly thinner than the originals, so I added some washers to compensate. The Axa dynamo is of the "swinging door" variety; it moves like a door until it makes contact with the wheel. It's imperative this type of dynamo is mounted the correct way around, with the forward motion of the wheel trying to open the door. Do it the other way around, and you risk the dynamo wedging itself between the frame and the wheel, which on a front wheel is potentially lethal. Dynamo and bracket sourced from Dutch Bike Bits (www.dutchbikebits.com).
