Friday, 10 August 2012

Nokia DC-14 Bicycle Charger

UPDATE: On October 2016 I switched to a hub dynamo, with dynamo lights - full details here

Almost exactly a year ago I posted about having fitted a Nokia DC-14 bicycle charger to my bike. There were, for me at least, many unknown factors, such as the surprisingly commonly held opinion that a bottle dynamo, such as what comes with the Nokia DC-14, wears out the sidewall on your tyre very quickly.
The Nokia DC-14

For those of you that aren't familiar with it, the Nokia DC-14 is a Nokia accessory, designed to keep Nokia phones charged while cycling. It comes as 2 components - an old-fashioned bottle dynamo, and all the circuitry enclosed in a water-proof unit that also serves as phone holder (by using really good elastic bands).

Now I've been using smart-phones since the early Windows Mobile HTC handsets came out, and with my job in IT, the ability to make and receive actual phone calls are NOT the most important aspect of my phone! To me, GPS functionality, various apps and finally a data connection is more important. Most Nokia phones don't meet my needs, as a result, and with the DC-14, this represented a problem.

Almost all Nokia phones use proprietary power connections, and the DC-14, being a Nokia device, out of the box only supports Nokia devices. Given that I haven't used a Nokia phone for almost 15 years, this was a problem to me. I overcame this by cutting off the end of the charging cable, and by soldering on a micro-USB connector, but apparently you can now buy a Nokia CA-146C converter that will change the connector from a Nokia one to a micro-USB.

The bottle dynamo when it was still mounted on my bike's front wheel
Initially I had the bottle-dynamo fitted to the front wheel, but later I moved it to the real wheel on my bike. Again, the standard kit doesn't allow you to do this, and I had to extend the wires from the dynamo to the charging unit. This was actually quite a simple job - far more tricky was positioning it so it wasn't in the way of my panniers, didn't rub against the rear mudguard and was still reachable to activate without stopping.

Over the year I have had the DC-14 I haven't been using it daily, for two reasons: firstly, I simply don't need to keep my phone charged daily while cycling and secondly, the bottle dynamo makes a fair bit of noise. Well, there is a third reason too - especially on uphills, I think I can feel the added drag, though that might simply be all in the mind!

When cycling longer distances I use it regularly (especially on downhills, when I see it as completely free power) and even on not quite long rides I'll use it, too, when logging my ride using Endomondo.

Now one of my biggest concerns when I bought the DC-14 was whether or not the dynamo would destroy the sidewall of my tyres. Some people even suggested it'd do so within a week! When I got it, I had a Schwalbe Marathon back tyre, and a cheap, no-name brand front tyre. A few months later I had to replace the front tyre, but not because of any sidewall damage! Instead, I replaced it as it was worn out by riding, and it its place I got another Schwalbe.

At about the same time I moved the dynamo to the rear wheel, where it's been ever since. With over six months' worth of reasonably regular usage, I still cannot see any sign of damage to the sidewall.

Overall, I think the DC-14 was a very good buy, and it proved itself up to keeping my phone charged even when cycling from Ilfracombe to Plymouth, along NCN 27.

That isn't to say I won't be making changes. I'd very much like to replace the bottle dynamo with a hub dynamo, which should work just fine with the DC-14 charging unit. However, I'm also thinking about a battery box holding 4 Ultrafire batteries, which will supply power to my phone and be topped up by the DC-14.

The battery pack uses 18650 batteries, the same as my head-torch that I use for cycling at night (1000 lumens of brightness!) and it means I can pre-charge four 4400 mAh batteries, which should be sufficient to power my phone for a few days, whilst using GPS!

In addition to keeping my phone charged, the battery pack will also be used to power my bike's rear light. Effectively, a DC-14 and the battery pack will give me the equivalent of a Reecharge, but at a fraction of the price. Changing the bottle dynamo for a hub dynamo means I won't have the noise of it running against the wheel, plus it will be more efficient.

I'll keep you posted.