Wednesday, October 23, 2013

Dynamo Lighting Systems


The benefits of using a hub powered dynamo lighting system are well documented, but for some reason have never become very popular in the U.S. Its hard to understand why, when these systems offer better visibility, more theft resistence and freedom from batteries and cold weather battery failure.

To get started we're going to need a front wheel with a dynamo hub. Options for the dynamo hub itself are plentiful with a wide price range from around $40 to around $350 depending on what you are looking for. From there you pick your spokes and rim (or work with one of our wheel builders to find the best wheel components for your needs) and then its time to build a wheel. As a side note, there are also several options for prebuilt dynamo hub wheels which may suit your needs, but a custom build will offer a broader choice of components. We are also more than happy to build a wheel for you ($45-$60 labor per wheel). You will also have to choose your lights. Again, many brands and models are available depending on how much light you need and what types of features you want.

For this project we will be using the following components:

Sanyo h27 hub. This is a great budget minded model for folks who dont have extreme demands on their lighting sytem.

DT Swiss champion spokes. DT ships their black spokes with aluminum nipples, which are okay, but I always encourage customers to spend a little extra on brass spoke nipples, they are less likely to round out or crack during service, they are naturally corrosion resistent and they have a much longer lifespan than alumimum at a small and exceptable weight penalty. Side note: DT silver spokes ship with brass nipples.

We are re-using the customer's stock Alexrims ID-19rim since this bike was only about 1 month old when they decided to upgrade to a dynamo system and the rim is in new condition.

This customer chose Busch&Muller for front and rear. The front light is the B&M IQ Fly RT and the taillight is the B&M Toplight Line Braketec Plus, both great choices for commuters, this headlight has daytime running lights and the taillight has a standlight which stay lit up when you are at a stoplight and also has a brake light which puts out a brighter light when your bike comes to a stop so that traffice around you knows what you are up to. Both add a lot of safety to urban commuting.

Using the Phil Wood spoke cutter

Preparing the spokes with a coating of Wheelsmith Spokeprep

Lacing the wheel

Finished wheel being installed in the fork

Wiring the light can be a bit time consuming if you have never done it before, so give yourself plenty of time, take it slow and pay close attention to how things are looking. Nothing is worse than spending a lot of time on a project and not liking how it looks at the end. You want to make sure that the wiring is secured along the frame, has strain relief where needed and doesn't interfere with any other components or moving parts.
The tools you will need are...
-wire stripper (preferably with metric crimps)

-Shrink Tubing (1/16" and 1/8" optional, but very helpful)
-Heat Gun (a lighter will work just fine)
-Various Wrenches (depending on what type of fasteners your lights have)

Side note: We are always more than happy to wire or re-wire dynamo lights for you in our service department ($17 labor per light).

Mounting the front light

Installing the shrink tubing to protect the wires and plugs

The rear light gets wired into the system

Now its just a question of running the wiring from the hub to the front light and from the front light to the rear ligth. Keep the wire secured to the frame out of the way of any moving parts. Make sure to have strain relief spots near and junctions to avoid damage to the wires.

That ziptie on the frame acts as strain relief. It allows the part sof the wire connecting to the hub to stay loose and flexible so that no stress will be put on the electric components.

Now, its time to go outside and try it....

Even with all the ambient light this headlight still shows up really well to oncoming traffic. You'll also notice the light patch in front of the bike. This really helps illuminate potholes and road debris. This light is fairly average dynamo light, but its performance surpasses all but the high end battery lights.

And here is a picture of the taillight in action.

  And here is a better photo of the light patch.

Thanks for reading.