Cycling UK Forum

I'd like to try navigating soley by GPS for an extended period and charging two AA batteries a day......somehow (un-supported by mains electrc!). Can this be done without having a full-on £200-£300 hub dynamo set up??! I've been trying to find a cheap-ish way of doing it but as far as I can tell a proper front wheel hub dynamo is the only option.....solar power looks a bit useless.

Does anyone have any experience of managing this?

Dave

I think you have almost answered you question,

If you are without access to mains for extended periods.......

Options?

Solar..... Lots of £ & you would need a 10 foot trailer.

Wind......Nice theory but a non starter.

Your Legs.....unfortunately in association with a Hub D.

I would also carry maps just in case.

Cheers,

Paul.

Search the forum for "USB charger", "iphone charger", "tout terrain plug", "eWerk", and also have a look at http://forum.ctc.org.uk/viewtopic.php?p=384832. I have the set up as per that thread, which works fine. Nokia charger (which includes dynamo) + USB cable to butcher + battery charger = under £50. But I have to say you might find it's actually a lot less hassle to carry spares and have a charging spree when you come across a plug somewhere. You can cycle all day trickle charging with a dynamo, or you can have an extended lunch stop by a mains connection and fast charge four batteries. It depends on your route and so on of course.

Busch and Muller Ixon IQ headlight
Busch and Muller RidenCharge
Dynamo hub wheel.

The whole lot can be bought from Roseversand and/or Bike24 for around 200 Euros.

This gives you an excellent headlight which if plugged to the dynamo via the Ridencharge will recharge the four AA batteries within it. Though slowly if you have the light on at the same time.

Thanks for the ideas. Hufty-your charging setup sounds pretty cool, I might give it a go! Would it fully charge two AA's from flat in a days cycling do you reckon? Would the Nokia supplied dynamo be sufficient or is the one you're using superior? And can it all be converted as you've done relatively simply???

I'm suprised there are no high resistance, quick charge dynamo or crank systems out there whereby you could just fit something to your bike and feel heavy resistance for say 20 minutes, but produce lots of power in a short period of time. Rather than having a slow trickle of power generation through the whole day....

Power Monkey Extreme for around £100 !!

This device might be worth a try if you don't want to go down the hub dynamo route.
You'd just need a USB to AA charger to connect to it and they are pretty cheap.

For the purpose of a tour, could you not use disposable batteries?

I have used a Silva solar charger when hill walking to recharge AA batteries for a previous camera. I don't remember precise details but I think it would charge moderate capacity cells in a fullish day of reasonable sunshine. I see that someone says the Powermonkey now does the same thing better. The attraction of this was its waterproofness and general outdoor practicality.
http://www.amazon.co.uk/Solar-Aa-Batter ... 63&sr=8-10

Dynohubs dont have to cost a lot of money I think the cheapest at rose is £53 build into a wheel

http://www.rosebikes.co.uk/article/atb- ... aid:203991
includes tyre as well

Have a look at this
http://www.amazon.co.uk/gp/product/B002 ... 03_s00_i00

Doesn't charge batts but it does charge up anything that plugs into a USB port.

Haven't used it a lot but intend to tour with it shortly for 1st time and charge my GPS unit.
The output is to a female, standard size USB port so you could plug in anything, iPod etc, into it
The output is from 4x AA batts. I guess those could be rechargable but some devises only respond to a fully charged normal set of batteries
I have found that most camp sites in UK sell AA batts so am gonna use this in emergencies (my hub only charges the GPS when I go over 6.5mph)

In past, before my hub/eWerk setup I have used a 'Silva Solar I' solar panel that charged up 4 AA batts in the dark UK summers in about 10 hours
Unreliable and adds a bit of weight, but it did save a bit of dosh in the long run.

Dave855 wrote:Hufty- Would it fully charge two AA's from flat in a days cycling do you reckon? Would the Nokia supplied dynamo be sufficient or is the one you're using superior? And can it all be converted as you've done relatively simply???

I only really used it to keep batteries topped up so I couldn't say how long it would take from flat. The Nokia website reckons that an 860mAh phone battery can be charged with 20 minutes of cycling, so for a couple of 2700mAh AAs that would be around 1hr 20 of >10kph cycling. That sounds slightly optimistic to me but it's way less than a day.

No reason to think the supplied dynamo can't cope but it would have been wrongly-handed for my bike. A dymotec has an efficiency of 40% according to the bummde website, which I assume is better than cheaper dynamos.

You don't have to use a USB connector of course but I decided that was what I was going to standardise everything to. I think the basic conversion is simple - cut the 2mm Nokia connector off the end of the charger and bare the wires, discard the male half of a USB extension lead, keep the female half and bare the wires. Connect them together observing polarity, away you go. All the rest of it was me going to town on robust connections etc. The bike bit worked fine straight away, the problems all came from the cheap USB wall charger, which I eventually resolved as per my thread.

Alex L wrote:For the purpose of a tour, could you not use disposable batteries?

agree, a set of these will last 8 days but I guess it depends how long the tour is?

http://www.amazon.co.uk/Energizer-Ultim ... d_sim_ce_5


.

My GPS (Bryton rider 50) works whilst it is charging and I have found that by having a cheap solar panel (http://www.amazon.co.uk/NEON-YG-020-Por ... 8&sr=1-176 for example) strapped to my rack and a lead along the top tube to my GPS keeps it fully charged and functioning (with the back light on permanently)in reasonable conditions. It will also power my (not iphone) mobile with a flat battery enough to make a call. I also carry 2 AA's and an USB charger as back up in case of bad weather.

The only problem I found was adapting the mount to attach the device whilst having a lead plugged in. HTH

I tracked my route through Africa (25,000km) using only rechargeable batteries in the gps.
If you turn off the gps when not cycling it can last about 3days (~24hrs use). So if you take 6 rechargeable-AA batteries you can manage 9 full days riding before having to recharge. And when that is not enough, just buy a couple of non-rechargeables to get you by.
There are not many places in the world where you cycle tour without having access to mains electricity for more than that. (It only happened a couple of times in 25,000km for me).

I would do this again over using a solar charger (power monkey explorer) which just didn't cut it.