Since the start of this year I’ve been making extensive use of a nifty on-the-road power solution from Taiwanese manufacturer Biologic called the ‘ReeCharge’. It’s billed as an effective — and environmentally respectful — way to put your pedalling efforts to use in keeping your smartphone, GPS or other USB-powered device charged while on the road.
I’ve given it a thorough road-test over the last few months (mainly while riding the Tern Link P24h folding tourer), and I’ll be talking in-depth about my experiences with it in this article. I’ll also talk about a couple of unusual alternative solutions I’ve come across along the way.
This piece will be of interest to anyone who regularly spends more than an hour or two on a bike and is looking for a way to keep their electronics up and running throughout, though I’ll be looking at it primarily from a touring perspective.
Who needs USB power on a long bike trip?
Well — nobody. People have been touring for decades without a whiff of technology to help them along the way. Nobody needs a GPS or a smartphone or an MP3 player or a compact digital camera or a GoPro. And even if they bring such devices along, so much of bike touring is spent off the bike that a simple mains charger is adequate in a great deal of cases.
Please bear with me while I reiterate annoyingly that a big trip, especially your first, will be all the better for cutting loose from these modern distractions. I spent three and a half years on the road without a GPS, a smartphone, or even a normal phone. I didn’t carry a laptop. Most of the time I didn’t have a map. I was utterly reliant upon my senses and initiative to find my way, and if something went wrong (which it often did), it was up to me to find a solution. This was an utterly invaluable learning process. Keep it simple. You don’t need any of this stuff.
But, for one reason or another, you have decided that you’d like to try taking one or more such gizmos with you. Of these, the most obvious beneficiary for a constant on-the-road power source is the GPS, or GPS-enabled smartphone, so I’ll look specifically at that application in this article, though I’ll cover as broad a range of other devices as possible.
Personally, I’ve been making use of a GPS this year in order to navigate between film screening gigs. Because schedules do matter in this case, I’ve been able to use a GPS to travel new roads in a predictable timeframe and on a relatively direct route, which are the kind of circumstances under which the real benefits of the GPS lie when on tour.
What does the ReeCharge system consist of?
Biologic manufacture a range of complementary products — generator hubs, power packs, phone mounts and other accessories — with the idea being that you mix and match depending on your specific requirements. At the core of the system, however, are the ReeCharge Dynamo Kit and the ReeCharge Power Pack.
The ReeCharge Dynamo Kit is the keystone, taking a current from a dynamo hub (a.k.a. generator hub) and converting it into a safe and stable power supply for a USB-chargeable device. It’s a small and unobtrusive little device which straps to a fork leg and requires no further attention in order to do its job.
(I’ll cover dynamo hubs in detail elsewhere, assuming for the purposes of this review that this prerequisite is in place, but it’s worth mentioning that Biologic make a very efficient and affordable dynamo hub, ideal as a foundation for new front wheel builds, called the Joule 3, which I’ve also been testing and will review later.)
While it’s possible to use the Dynamo Kit alone to take a power supply direct from the source to the device, the ReeCharge Power Pack is designed to complement it and fill in a variety of gaps when you aren’t pedalling (at a junction, on a break, for the night) and want to prolong the power supply. It acts as an intermediary, taking the current from the Dynamo Kit and storing it for later use in a built-in lithium polymer battery — in effect, an offline back-up power source. We’ll look at where this comes in useful later on.
I’ll be reviewing these two complementary products — the ReeCharge Dynamo Kit and Power Pack — together, as it’s only when used in tandem with each other that the genuine benefits of the system become clear. When you buy the Power Pack, you’ll also get the Dynamo Kit in the box, though the latter is available separately.
Who is the ReeCharge designed for?
While I have much to say on the topic of over-equipped, over-technologised adventures, it’s a fact that many bicycle travellers these days are packing smartphones, GPS units, e‑readers, compact digital cameras and other electronic gadgets.
Smartphones in particular are becoming a popular choice for navigation, simply because their built-in GPS systems and the software freely or cheaply available to use them has caught up with standalone GPS units.
In fact, it could be argued that a well-configured smartphone makes for a better navigational tool than a GPS unit because it gives its user the ability to multitask and to use a constant 3G/4G internet connection for route calculation, modification and even logging via apps such as MapMyRide (Android / iOS App*) or TrackMyTour (iOS App*).
The problem, of course, is that smartphones suck up battery power, particularly when GPS and data connectivity are in constant use and the screen and backlight are permanently powered up. You’d be lucky to get a morning or afternoon’s worth of use from a smartphone in this way. The result is coming to the end of your ride with a dead battery. If you’re on tour and camping is your staple overnighting method, this is a real issue. And herein lies one of the ReeCharge system’s greatest benefits.
Imagine setting off in the morning with a detailed, up-to-date digital map with which to navigate all day, and knowing that even after the five or six hours pedalling and navigating and all the breaks you took along the way, your smartphone or GPS unit will still be on 100% charge — AND that you’ll have a fully-charged backup power source with which to top up the batteries of your e‑reader and digital camera that evening from the comfort of your tent.
A system like the ReeCharge, which delivers all of this through the simple process of flicking a switch and pedalling all day like you would do anyway, theoretically has the ability to shift the daily routine of a gadgetised touring cyclist to one that no longer includes the constant worry about batteries running out, nor the extended lunch breaks and awkward conversations with restaurant proprietors about plugging a raft of stuff in to charge. If all goes to plan, you’ll have power all day for your navigation device, be that smartphone or standalone GPS, and a way to charge your other bits and bobs in the evening, even when you’re camping for days or weeks on end.
(A word of warning: no traveller should ever rely entirely on electronics. A smartphone or GPS unit is no substitute for a map and compass — and, more importantly, an awareness of how to function comfortably and calmly in a world in which all these modern conveniences are absent. I mean this. If you can’t navigate on wits alone, and your loved ones can’t go for more than a few hours without hearing from you, you really need to stop reading and resolve this first.)
What’s included in the Biologic ReeCharge Power Pack kit?
(This refers to the kit available from Evans Cycles*, who are Biologic’s primary UK stockist.)
You get the Power Pack and the Dynamo Kit. But it’s the cables and adapters that make the difference as this is what determines the system’s real-world usefulness in conjunction with your own devices.
On this front, the following are included in the box:
- Retractable device cable (onto which you fit the relevant adapter)
- Apple connector (into which you plug your original Apple cable)
- Sony Ericsson adapter
- Samsung adapter
- Late-model Nokia adapter
- Mini-USB adapter (almost all your generic USB devices, including GoPro, many cameras, e‑readers, etc)
- Micro-USB adapter (many Android phones including HTC)
Theoretically it’s possible to plug any other proprietary USB charging cable into the Apple connector and have the device charge up too, as the power pack outputs a standard 5V USB supply for up to a 850mA current draw.
There is also an innocuous looking piece of transparent rubberised silicone in the box. Far from being simply a disposable part of the packaging, as I originally thought, this is actually an ingenious shock resistant handlebar mount for pretty much any handheld device in dry weather. I’ve used it with a couple of smartphones and a GPS unit and it’s possibly my favourite part of the whole kit.
How do you set up the ReeCharge?
The Dynamo Kit consists of a power regulator with cables to connect it to your dynamo hub at one end, via a standard power connector, and to the Power Pack at the other.
It’s designed to work with sources outputting a standard 6V at 2.4 or 3.0 watts. For the sake of completeness, that includes not just Biologic’s own Joule II, Joule 3 and Joule HG hubs, but also the Schmidt range of uber-fancy SON dynamo hubs, SRAM’s and hubs, Shimano’s current DH-3N80 and DH-3N72 hubs, and the SunUp Eco DS1‑R, which you haven’t heard of but which I’ll mention later on.
A dynamo hub is the only pre-requisite for using the ReeCharge system. Some trekking, touring and city bikes, especially from continental Europe, will have these as standard. Otherwise, it’s a chat with your local bike shop’s wheelbuilder, or of course the DIY wheelbuilding option.
(And even that’s negotiable: I decided to see if the system would work using an old-fashioned bottle dynamo. Did it? Yes. This is officially supported by the manufacturer, if you’re wondering.)
Having hooked up the Dynamo Kit to the hub, the other cable connector mates with the ReeCharge Power Pack. This features a rugged silicone casing into which is built an adjustable mounting strap. The idea is that you can strap the thing to your head-tube or stem, but easily disconnect the cables and take it with you in order to use it as a power pack. You’re expected to stow the cabling as you would for a cycle computer, either by wrapping it around other bits or cable-tying it to the frame appropriately. Not exactly rocket science.
Having done this, the input and output connector ports face downwards, which together with the weather-proof seals concealing the Power Pack’s connectors is how all of this stuff stays functional in a downpour. Orienting the Power Pack towards the direction of travel also allows the battery indicator LEDs (thoughtfully, white) to be used as emergency visibility lights. Nice touch.
All that’s left to do is mount your chosen device to your handlebars via the method of your choice, choose from the range of connector adapters (mini USB, micro USB, Samsung, Sony Ericsson and new Nokia — Apple users can use their own cables), plug up, and you’re ready to go.
Though a clever little wraparound silicone universal device mount is included in the package, it’s not exactly going to weatherproof an expensive smartphone. Biologic make their own weatherproof handlebar mounts for the iPhone and a selection of Android smartphones. I’ve yet to try any of these myself, preferring the silicone strap method, the rubber band method, and not cycling in the rain.
It’s all pleasingly uncomplicated, even if there are quite a lot of cables to fiddle with, especially if you’re already got a cycle computer and a dynamo-powered lighting system on the go. But hey, that’s what cable ties are for. No extra marks available for presentation.
How does the Reecharge perform in real life?
For the sake of realism, let’s amalgamate all of my experience with this unit (almost a year of regular use) into a single hypothetical day on the road and overnight camp.
I mount my phone on the handlebars, plug in the power input cable with its appropriate connector, and fire up my navigation app of choice (Backcountry Navigator, for the sake of example).
I attach the Power Pack to the head tube with the quick-release strap, plug in the power input cable from the dynamo, plug in the power output cable alongside it, and switch on the unit’s power input mode. Now, when I begin pedalling for the day, I’ll see a green LED illuminated on the side of the unit, which indicates to me that it’s receiving power and therefore charging its internal battery. I check the level of the battery by giving the middle button on the power pack a quick press, which illuminates between zero and three white LEDs to indicate the remaining charge.
If the unit is fully discharged (for example because it’s been used to charge up several other devices the previous night), I’ll probably ride for an hour in this state to put some juice back into the power pack. I’ll run the phone or GPS on its battery during this time. This is because, when the pack is discharged, there won’t be a continuous power source to the device in the case of stopping the bike. Give it a little charge, however, and the unit will continue providing power to the device when I stop the bike by switching to its internal battery. Stable and continuous power is generally a better idea for maintaining longevity with lithium cells (i.e. those used in almost all modern USB-powered devices) than short, broken bursts of charge.
If there’s some charge present in the pack already, however, I can switch on the power output immediately. Now, my device is running on external power via the ReeCharge. While I’m pedalling, this will be coming directly from the dynamo, via the power pack. If I stop for a break, or at a junction, or whatever, power will continue to be supplied by the pack. Additionally, if the current required by my device is not onerously high (though with the meatier smartphones it may be), the power pack will gradually gain charge at the same time.
The long and short of it is that my navigation device will be externally powered, and having its own battery charged, during the course of my morning’s riding. The ReeCharge Power Pack will likely be getting some charge as well. And I won’t have to worry about switching everything off for short breaks in riding, because the backup power supply will kick in automatically.
By lunch, my device should be approaching full charge, if not already there. (There’s a mains power adaptor included, by the way, which might well be used at lunchtime to top up the power pack if the facilities are available.)
In a rigorous and highly controlled test, I take a HTC Desire HD — a notoriously power-hungry smartphone — and charge it from 7% charge to 50% in one morning of riding. This was using an inefficient bottle dynamo, with the phone’s GPS function switched on and with MapMyRide and Backcountry Navigator running simultaneously. With a modern hub dynamo, better results will be obtained. (Note that I did have Flight Mode on to disable the 3G network connection, which is not exactly necessary when you’re pedalling.)
When it comes to lunch and thus a longer break, I’ll switch off the power output of the power pack. This has to be done manually using the same switches, and the change will be indicated by the red LED turning off.
And this is where I run into one of the unit’s few (and luckily minor) flaws. You see, accurately reading the state of a tiny red LED in the direct light of the midday sun is impossible. I have to cup my hands around the unit and squint in order to make out whether it is on or off. Not just that, but the buttons on the front are ambiguous in their state — by which I mean there is no positive feedback, visual or tactile, to indicate whether a button press has resulted in the unit being switched on or switched off.
The same is true for the power input switch, and the green LED is even less visible than the red one. And since the only way to illuminate the green LED is to have the dynamo create a charge, I soon find myself in the awkward position of trying to lift the front wheel off the ground with one hand, spinning it with the other, and then rapidly cupping my hand around the power pack in order to see whether or not the green LED has come on — by which time, once I’ve got the angle right and blocked out enough sun, the wheel has stopped spinning. (Riding the bike whilst bending down below the handlebars is obviously not recommended.)
These are minor problems. There are workable solutions, and they don’t impede the core functionality of the unit. After a lot of use, I have become sensitive to the buttons to the point at which I can tell their state by pressing them, but it’s a very delicate discernment to make. There is also the more reliable method of plugging a device into the Power Pack and seeing how it responds to a press of the relevant button, as almost all devices will indicate clearly whether or not they are receiving external power. Lastly, on overcast days and in the mornings and evenings (and at night, should you fancy it), making out the LEDs is not half as difficult.
But it is something Biologic might note for future incarnations of the design. There’s no point wasting power on LEDs, so my suggestion would simply be using switches that provide unmistakeable feedback as to their on/off state.
Once fully charged, any modern device will only draw enough external current to keep itself powered up with the battery remaining at 100%. Thanks to the ReeCharge Power Pack’s smart circuitry, this surplus pedal power will be used to charge its own internal battery. The result, at the end of the day’s ride, is likely to be a fully-charged device ready for the following day’s ride, and/or for a little communications use in the evening in the case of a smartphone — AND a more or less fully charged power pack. This is where we get to see the beauty of the intermediate power pack system.
I’ve removed the power pack from my headtube by unplugging the connectors and undoing the quick release strap. At this point, of course, I’m probably in my tent/hammock/mosque/drainage pipe, getting set up for the night. Here’s my opportunity to use that stored-up pedal power to top up my other devices.
Let’s say I’ve got a GoPro mounted to my handlebars, and I’ve drained the battery in the mistaken belief that anyone else will be interested in watching countless hours of nondescript asphalt going past in slow motion. Will the ReeCharge be able to, er, recharge said camera in order that I may tomorrow film more of the same?
The answer is yes, as demonstrated by another rigorous test in which I plug a fully discharged GoPro HD Hero into a fully charged ReeCharge Power Pack and hit the power output switch. It takes 2 hours and 15 minutes to fully charge the GoPro, leaving enough juice in the Power Pack to get other mission-critical systems up and running again the following morning. (It’s worth mentioning that a realistic day’s filming routine would only drain a GoPro completely if there was an extremely long timelapse or accidental button-press involved.)
How about if I’ve got a drained smartphone on my hands?
In yet another real-world test, the same HTC Desire HD is charged from 3% to 70% by a fully charged power pack.
A Nook Simple Touch e‑reader’s battery is similarly taken from 40% charge to 100%, using less than half of the Power Pack’s capacity in the process.
(E‑readers like the Nook*, of course, can last weeks on a single charge, and when hacked to offer basic Android tablet functionality can be very handy and extremely inexpensive things to pack for a bike tour.)
Bear in mind that this is all after having charged and powered a navigation device for the duration of my day’s ride. I am hoping that these examples of real-life use will be sufficient to give a clear idea of the system’s capabilities, though your mileage will of course depend on which and how many devices you use, as well as how you use them.
While I have not tested the unit in laboratory conditions, nobody actually goes cycle touring in a laboratory, and those who test equipment in such a way are usually better authorities on life in a laboratory than life on the road.
What about dynamo hubs and ReeCharge compatibility?
None of this is any use to anyone who doesn’t have a dynamo hub (or plain old bottle dynamo). In the UK, it’s fairly uncommon to get a new bike with one of these fitted as standard, except on city bikes for which they’re sometimes fitted for powering lights.
What this means is that you are quite likely to end up looking at aftermarket generator hubs, rather than gleefully plugging the ReeCharge into your existing, underused dynamo hubs. While I can only personally speak for the effectiveness of three of these hubs, all of the ones I’m going to list here will in theory do the job, and there’s no reason to think they wouldn’t. Some will do the job more expensively than others. of course. And on a fully-loaded touring bike it is highly unlikely you will notice any additional rolling resistance from any of them.
If you really want to read more about current output and efficiency figures and stuff, the CTC’s Cycle magazine recently published this article, which takes clinical empiricism to a whole new level. (Don’t say I didn’t warn you.)
Most local bike shops will be able to build a complete wheel onto your hub — a good opportunity to specify rims at the same time. Sun Ringle CR-18s* are a good choice for 26″ wheels.
Biologic Joule 3 / Joule HG
The Joule 3 is a relatively new offering from Biologic, designed with the Schmidt SON Dynohub (the Rolls Royce of generator hubs) as the performance and efficiency benchmark. Available in a 100mm OLD / 32-hole model, it’ll suit all but the most paranoid and heavyweight tourers who absolutely insist on 36 spokes per wheel. I’ve been using this all summer and it’s the hub I’ve used for most of my testing for this article. The Joule HG is an older model that can be switched off mechanically, virtually eliminating drag. They retail at around £120. It’s a shame they seem so difficult to source in the UK. I can’t even find them on eBay*.
Shimano Budget Dynamo Hubs
Shimano, eh? They don’t half make it difficult for us. Five billion permutations of the same thing, whichever direction you turn. Their budget options for generator hubs are the DH-3N20 and DH-3N30. They will work with the ReeCharge. They might break sooner than the pricier ones. (Or they might not.)
Shimano High-end Dynamo Hubs
The current established high-end Shimano models are the DH-3N72* for rim brakes (~£70) and the DH-3N80* (32h/36h) for disc brakes (~£90). They’ve been widely used and can be considered tried and tested on tour. Shimano have just released another billion new variations under the XT line, but it’s probably best to ignore them until the market settles down again.
Schmidt SON Dynohub
If you just can’t help yourself, the German-made Schmidt SON Dynohub enjoys a reputation as the hands-down best dynamo hub money can buy. Why you’d blow £200–300 on one is beyond me, but I’ve included it here for the sake of completeness. SJS Cycles have them, if you really must.
And now for something completely different…
I was introduced to the Taiwan last year, and I have taken it for a series of test rides since then. The big difference with this rather innovative generator hub is that it can be fitted to an existing rear wheel with no modification — thus, no wheelbuilding. It outputs 6V at 3.0A, just as the Shimano and Schmidt offerings do. The only caveat is having to undo a single hex bolt in order to remove the rear wheel, though it’s hardly a deal breaker on a long tour.dynamo hub in
You’ll be hard pressed to find one in a shop here, but thankfully they are available direct from Taiwan via eBay* for just under £80, including postage.
If you’re dreaming of your first big adventure: forget all of this rubbish, get a bike and leave already. Here are the 3 basic steps. Keep it simple. Enjoy.
If you’re absolutely sure you want to get into all of this gadgetry, and you’re looking for a reliable, versatile power solution compatible with all popular dynamo hubs and the kind of devices you might take on tour, the ReeCharge system performs this function and performs it well. It’s not 100% perfect, but minor niggles can be overlooked given its simplicity and effectiveness in getting the job done.
In the UK, I’d head to Evans Cycles’ website* to get mine. They’re currently doing it at 10% off — and yes, all the accessories mentioned in this article are included. (Not the hubs, though.)
In the USA, Biologic’s outletstock the ReeCharge.