The Bike2Power LightCharge USB charger is designed to work with a dynohub putting out 6 to 12V AC and supplies a regulated 5V DC up to 250mA through a standard USB connector. The LightCharge consists of the unit itself with integrated cable and a bunch of cable ties for attaching it to the frame.

The unit is remarkably compact compared to similar devices I’ve seen and used; not much bigger in diameter than a 50 cent piece. It has two push buttons to toggle between using the unit to charge via the USB port or to direct all the power to standard dynamo lights – in effect switching the charging facility on or off. The buttons are weatherproofed by a soft plastic cover. LEDs indicate which switch position has been selected.

The USB port is the standard size and has a cover to keep out dirt and water when it is not in use. When a USB plug is inserted it is a snug fit, but one should position the unit carefully to minimise the chance of water getting in or the plug shaking loose.  Placing the port horizontally would possibly be the best option.

The back of the unit has a plastic mounting block that is concave to fit on to most standard diameter tubes or handlebars. There are slots in the block for cable ties to secure it to the frame. As an example, I mounted the LightCharge on the underside of  the handlebars,  underneath the Garmin mount.

A three core cable comes out of the unit which is  long enough to run all the way down the forks to the dynohub. Two of these wires connect to the dynohub. If you have a Shimano dynohub the bare wires attach straight into the Shimano connector. If you have a Schmidt dynohub (as I do) you need to terminate the wires with spade connectors (not supplied). The third wire is terminated with a crimp joiner. The idea is to crimp the open end onto the wire leading to your headlight.

My setup is a bit different to the usual. First of all I don’t like having two sets of wires running down the fork. So instead I have a kind of extension cord running from the dynohub to the top of the forks that terminates with spade connectors the same as on the dynohub. Also, I like to run my lights all the time and the dynohub can run my lights and charge my Garmin at the same time. So instead of connecting the third wire to my headlights, I wired the headlights in parallel with the LightCharge. If I want to disconnect the LightCharge so it does not draw power, I use its switch as an on/off switch. If I want to run the LightCharge with full power, I can simply switch off the headlights.

For my first ride I just threw the unit into my handlebar bag and grabbed a retracting USB cable with a mini-B end to connect the LightCharge to my Garmin Edge 705. I set out along the Main Yarra Trail and Diamond Creek Trail towards Diamond Creek. These trails are largely unsealed and a bit bumpy so a good test for the mechanical connections. The LightCharge worked as advertised; the LED indicated correctly the switch setting and kept the Garmin charged while I also had the lights running.

I once calculated that the Garmin draws about 0.3W or one tenth of the dynohub output which is why I can run  the lights and keep the Garmin charged at the same time. Other devices may draw more power so this might not work for them. Also, keeping the Garmin topped up is one thing but recharging it is another thing altogether. I did a rough test where I allowed the Garmin to discharge about one third (the only gauge of this is a picture on the screen so it’s hard to be precise). With the LightCharge connected and headlights off I rode around and after about 2.5 hours gentle riding the Garmin was almost fully charged. This should give you the idea that fast recharging from a dynohub is not to be expected. One thing I did not test was recharging from completely flat. From experience, this is not usually very successful and the Garmin certainly wont operate until some minimum charge level is reached. In those situations you are better off recharging it with a PowerMonkey or equivalent.

A slight digression here for Garmin owners. The Garmin is quite picky about the type of USB cable you use. Basically, depending on how the pins are set up, it will decide if it is connected to a charger or connected to a computer. If it thinks it’s connected to a computer, even if only charging, it wont record your ride or show your data. Alas, my retracting cable was not set up properly and partway through the ride the Garmin switched into “computer” mode. Luckily I had also brought a proper Garmin cable just in case. I preferred the compactness of the retracting cable but I really wanted to record the ride and see the data. A quick cable change and all was well.

The LightCharge is compact and lightweight. The standard USB port makes it more versatile than units that use proprietary connectors, and it’s switchable so you can be sure your lights work when you need them or you can charge with full power if you want. Just be careful how you mount the unit to keep the USB port protected from the elements when it is in use.

The LightCharge Hub Dynamo USB charger is available for purchase online from Bike2Power for $67.95 (USD)

Some people like to listen to music while riding, I prefer to crunch numbers. Seriously. The Garmin and the iBike both provide a vast array of data and even the camera tells me the time of day. Aside from providing some useful diversion to pass the time, these devices have practical uses as well. From just riding around to competing against the clock, having the right data from the right gadgets helps me to get the most out of my cycling.

Just riding around

Most of my riding is “just riding around”. I usually work from home, so I need to take opportunities to get out for a bit of exercise and fresh air. On working days the most important information is the time, as I often have a window of opportunity between teleconferences to get out. Of course I could use a watch, but why look at your wrist when you can look at your handlebars? They’re right in front of you.

My main reason for riding is to keep my weight under control, so I want to know how many calories I’ve burnt. The Garmin Edge 705 calculates calories burnt but is notoriously inaccurate. The data provided by the iBike is based on power output and is thus more reliable. It’s a great feeling to see you’ve burnt 300 Calories from a ride to Studley Park Boathouse then wipe it out with a yummy ice-cream.

Tracking calories burnt is a bit of a chore so to keep things simple I set myself a target distance to ride per week and I record distance travelled per trip. I can download that from the Garmin onto the Garmin Training Centre in order to track by week, month or year. I know from my analysis that I burn between 15 and 20 Calories per km depending on the intensity of the ride. That equates to a couple of grams of fat per km if I don’t indulge in those ice creams.

On weekends I like to explore new routes so my riding doesn’t become monotonous. For those rides I need to know where I am so I don’t get lost, and where I went so I can incorporate the ride into my mid-week schedule. The Garmin has a map with GPS navigation and records the ride into a file. I’m a keen mapper for Openstreetmap and use the GPS traces to record new roads and paths. For the more complicated routes, I plan them out first and load them onto the Garmin. Occasionally I use the navigation feature if I get a bit lost. I point to where I want to go on the map and ask the Garmin to take me there. It works best in this scenario over short distances.

Commuting
I occasionally go to the office for administrative stuff. As an infrequent commuter I have to carry everything with me. I used to commute in lycra then shower and change at the office but that means taking a complete change of clothes and towel as well as my laptop, security pass and other paraphernalia which in turn means remembering to do all of that. All too often I’d forget one thing or another which meant  turning around and going home for it. These days I commute at low speed in normal clothes and aim to not work up a sweat. That means I only need a pair of shoes (I ride with SPDs) and my laptop and pass.

The most important thing to know when commuting is the time, in order to know if you are running late or not, or whether you’re about to encounter the school run or heavy traffic. Distance can be useful so you know how far you have to go, but on a regular route you should already know that. When aiming to stay cool a power meter is incredibly useful. I aim to keep my power output under 100W, except for the steepest pitches where my limit is 150W, and that only for short stretches. One does have to get to the office in time after all. Cadence can also be useful to maintain discipline. It’s often harder, mentally, to ride slowly than to ride fast.

Training
Training for me means preparing for a specific event like the Alpine Classic. The single most useful data for this is power. Power meters let you train without having to replicate the conditions of the event. Climbing a mountain at speed requires a certain amount of power over a certain amount of time. You can train to produce the same amount of power on the flat for the same amount of time.

When I was training for the Alpine Classic I realised I might no be able to generate enough power for the final climb up Buffalo at my normal pace, so I needed to train how to climb at low power output. This means riding slowly uphill and is more about technique. For this, things like gradient, speed and cadence can be useful.

Before I had a power meter I used a heart rate monitor, but no longer bother. Power is much more responsive to your efforts and there are a huge number of tools out there for training with power. They usually centre on your FTP or functional threshold power. This is how much sustained power you can produce for one hour. One way to calculate it is with a sustained 20 minute effort with a power meter.  The iBike has built in workouts that you can then follow for different purposes.

Randonneuring
I don’t do any competitive cycling but I do Audax rides which are against the clock. The most important things to know on these rides are: how long have you been riding, and how far have you gone. The organisers provide cue sheets, but having a map of the route is also useful. Riders have been known to go off course. The Garmin takes maps that I build from Openstreetmap data.

Being endurance rides it’s important to conserve energy and last the distance. The biggest aid for that is power output. When I’m doing a hilly or undulating ride I’ll set myself a maximum power target and try to stay below that. Cadence can be useful to make sure I’m in the right gear and spinning rather than grinding. Knowing the headwind let’s me know if I should be in the drops and also helps find the sweet spot when drafting. Gradient helps me to understand why it’s hurting or why I’m going so slow.

The Garmin has a nice feature of alerts based on distance or time. I usually set an alert every 5 minutes or so to remind me to take a sip of water. I have a bad habit of not taking enough fluids when I’m on a long ride, so having a frequent reminder is a big help.

Touring
When touring the most important thing to know is where you are and how far to your next stop. Knowing the time is also important in case you need to get to the destination before it gets dark, and your average speed so you can estimate how long it will take. On hilly tours gradient can be useful for very steep sections so you know if you need to dismount and walk before coming to a grinding halt and clip-stacking.

If it’s important to conserve energy for days of long touring then power, cadence and headwind can be useful. Knowing how many calories you burnt can also be useful so you can be sure to replenish before the next day’s riding. In general I prefer to minimise the gadgetry on tour as it is one more thing that could go wrong and distracts from the joy of just watching the scenery

It’s great to have a video camera going as you ride along. You never know when something unusual will happen, like a lyrebird running in front of you. My camera set up works well for tours as it has a long battery life and recording capacity.  The camera batteries last over 20 hours and being AA cells are easily replaced when they go flat. The mini-DVR battery lasts about 4 hours but can be supplemented with a Powermonkey and recharged at stops with a plug in USB charger which is not a burden to carry around. In theory I could power the miniDVR from the dynohub but I’ve not yet tried that.

After the ride you want to know where you went for posting on blogs like crazyguyonabike. The Garmin lets you download the GPS trace for the route. Some stats like average speed, and calories burnt can be useful for planning future rides.

The Gadgets

Computer
The Garmin Edge 705 has been superseded by the Garmin Edge 800, but even though I love new gadgets I also like to make them last as long as they can and a bit more.The 705 has a multitude of features: speed, cadence, heart rate and power from ANT+ devices. A barometric altimeter gives altitude and calculates gradient. It tracks routes on GPS and also provides navigation with either the supplied maps or DIY maps you can build from Openstreetmaps.

Power meter
For the last few years I’ve used an iBike iSport which I am now upgrading to the new iBike Newton. The iBike is a “reactive force power meter” which means it determines power output by measuring the forces reacting acting against you as in Newton’s law “for every action there is an equal and opposite reaction”.  The forces it measures also provide additional information to the cyclist: an accurate gradient using an accelerometer, and wind strength

Camera
The camera is a model 21CWSHR “bullet cam” from RF Concepts (UK) which is a Sony CCD 480TVL 1/3″ colour camera with a 8 mm lens. A bit dated now but it does the job and, importantly, the external battery pack provides over 20 hours of continuous use from 8 AA cells. It is in NTSC format of 768×494 pixels and works well in low light with sensitivity of 0.5 lux @ F2.0. This type of camera can be mounted onto a helmet, hat, bike or just about anywhere and records onto any suitable recording device.

The recorder is a CC-KL509 Mini DVR with 16Gb SD card. My choice of the miniDVR is a result of evolution. I started recording fishing videos from the bullet cam onto a digital tape camcorder. The tapes only allowed 1 hour of recording even though the battery life was great at 9 hours. As technology improved I replaced the camcorder with an Archos AV-500 DVR with 80Gb hard-drive. The Archos battery life was about 4 hours and it had plenty of storage, but hard-drives don’t like rough treatment. The KL509 also has about 4 hours battery life that can be recharged via USB and the 16Gb SD card can hold about 12 hours of video. And of course it’s easy to carry around extra cards.

I’m always on the lookout for new and interesting ways to enhance my cycling experience. If you have a different gadget, or even novel ways to use the same ones I’ve got, post a comment below. Of course, having all this data is only useful if you can do something with it. Analysing it and planning ahead based on what you find is a story for another day. Keep an eye out for further instalments.