Author Topic: Pedal Cell  (Read 6948 times)

tt2cycletours

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Pedal Cell
« on: April 15, 2022, 05:37:30 PM »
Hi, has anyone tried using this system? Looks an expensive option as an addition, but I like the idea of leaving the hub dynamo to power the lights, and having another device to handle charging/powering devices.

https://pedalcell.com/

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tt2cycletours

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Re: Pedal Cell
« Reply #1 on: April 15, 2022, 05:44:38 PM »
Here is a useful article on these modern rim dynamo systems:

https://www.cyclingabout.com/rim-dynamos-can-now-generate-more-power-than-hub-dynamos/
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mickeg

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Re: Pedal Cell
« Reply #2 on: April 16, 2022, 11:38:24 AM »
Hi, has anyone tried using this system? Looks an expensive option as an addition, but I like the idea of leaving the hub dynamo to power the lights, and having another device to handle charging/powering devices.

https://pedalcell.com/

I have no experience with that device.  I assume this question is for bike touring where you do not have access to an outlet (mains) every night.

Bike touring, I rarely use a headlight.  My last bike tour (five weeks long) I did not bother to install a headlight on the bike.  Instead I had one that attached to my handlebar with an elastic that I could plug into a powerbank if I needed a light for an evening ride to the pub or for a tunnel. On that tour I only used my dynohub with a Sinewave Revolution to charge batteries.  Never did need the headlight.

I usually have a AAA powered taillight flashing when touring, occasionally two.

I wrote up a piece on my electrics on that tour where I did not use any dyno powered lights at this link if you are curious:
http://thorncyclesforum.co.uk/index.php?topic=13696.0

I have installed dyno powered lighting on my light touring bike, if I use that bike on a tour the lights will remain installed.  But I expect that the lights would almost always be off while I prioritize battery charging.


martinf

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Re: Pedal Cell
« Reply #3 on: April 17, 2022, 07:36:43 AM »
The Pedal Cell seems to be a good option for charging electrical gadgets, not so good for lighting.

The Velogical rim dynamo would be a very good option for someone who wants fixed lighting, but doesn't use lighting much in daytime. For that kind of use it would be better than a hub dynamo as there is no drag when the lights are off. I'd be wary of using it in muddy conditions, and if used constantly in daytime you would eventually have the issue of wear, starting with the O-ring every few thousand kms, and maybe in the long term the dynamo itself, as it spins much faster than a front hub. In my experience, decent dynamo hubs last for several tens of thousands of kms, so in that respect they are no worse than ordinary front hubs.

As always, there is no "free" power, so if using the Pedal Cell's high output option the drag will probably be noticeable. I used to notice the drag from the relatively inefficient old Soubitez and Miller tyre dynamos I had in the 1970's, but I don't notice it with my recent hub dynamos, and didn't notice it with the efficient B&M S6 tyre dynamo I had in the 1990's.

My own choice is almost the exact opposite. I have hub dynamos on all bikes, powering LED lamps that dont take much power, so they don't generate much extra drag. I generally leave the lamps on all the time, as I reckon they give a slight safety advantage when riding in traffic, so a rim or tyre dynamo would not be a particularly good choice for me. And I don't need to charge anything, as the electrical gadgets I currently take on tour are:

- a rechargeable battery-powered front lamp that I use as a flashlight for camping, in normal use this is good for over a month without recharging,
- a 2005 vintage dumbphone, whose battery lasts me at least 10 days in normal use, so with 2 spare batteries that weigh about 25 g each I am good for a month touring,
- a small digital camera. I generally don't even use up the first battery, but like the dumbphone I have 2 spare batteries that don't weigh very much.

When I eventually upgrade to a smartphone with GPS, I will probably go the powerbank route, with a fairly big and heavy battery, which I would charge every few days when staying in hostel/hotel accommodation, which I generally do anyway even when on a mainly camping tour.


mickeg

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Re: Pedal Cell
« Reply #4 on: April 17, 2022, 10:50:47 AM »
To clarify, my previous comments were solely oriented towards being on a bike tour, then my priority is charging batteries from my dynohub.  Dyno powered lights are almost always off.

But riding near home, my dyno powered lights are usually turned on.  Last year I added dynohub to my fourth bike, now have dyno powered lights front and rear on those four.  When near home I can charge up my GPS while at home, thus my lights are usually on. 


PH

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Re: Pedal Cell
« Reply #5 on: April 17, 2022, 09:14:39 PM »
I have no experience or knowledge to share, but they do look a fantastic bit of kit.  The question is do you need what they offer?  You already have a dynamo, which if I've understood is redundant while on tour, which might provide what you need more economically.  I bought a secondhand Igaro USB charger that attaches in minutes with a couple of re-usable zip ties and comes off again when not needed.

tt2cycletours

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Re: Pedal Cell
« Reply #6 on: April 20, 2022, 10:38:09 PM »
Many thanks for the responses. 

I am heavily reliant Garmin Edge 800/1000 for navigation, neither with great batteries, so I am rather dependent on dynamo support or battery back up to get through a long day.  I have also once been in the situation of cycling through the night*, in Switzerland, with my lights off to get enough power to my Garmin so I know the way!  Don't worry, I put the lights on when I saw a police car.

I am currently preparing for LEL, and although an extra supply of electricity is appealing, the weight of the pedal cell puts me off, although the bottle dynamo mount on Thorn frames may save a bit of that.  I think I will not be able to run navigation and lights for a whole day including some evening riding, and so will need a back up battery, which I can easily charge at any sleeping stops.

For general touring, dynamo should be enough for navigation with emergency battery and charging it at campsites.

I am quite keen to configure some switches in a project box (along with voltage regulator) so I can control where the power from the dynamo goes (output) on the go... including switching between the inputs of battery bank/dynamo/charging via mains.  Something I can use on the go, and all in one water tight box to strap onto bar bag.

Interesting to see how some tourers manage to get away with more battery efficient navigation/phones/lights/cameras, and the taking of spare batteries. 

Thanks for the link - lots of useful stuff on there.  I love the USB voltage reader, would be great fun to have a read out of dynamo output on the go... I assume this would have to be connected after the velocharger.

Looking at the velocharger instructions, it says at speeds of over 40mph you will damage the device.  Annoying, I thought I was buying this to avoid this been a problem - bit disappointing. 

I have previously had two Ewerk power supply units fail - I have used them in the alps... and you can get up to 40mph on the descents; does anyone think that might explain why the units have failed?  Should I be surprised?  Or is the life span limited on these products.


*Since reading M Walkers Why We Sleep, I am reappraising cycling through the night!
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Danneaux

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Re: Pedal Cell
« Reply #7 on: April 20, 2022, 11:39:24 PM »
Quote
Interesting to see how some tourers manage to get away with more battery efficient navigation/phones/lights/cameras, and the taking of spare batteries.
I'm a bit old school I suppose, but a strategy that works well for me is paper cue sheets. I used them long (i.e. 45 years ago) before consumer GPS units were available and they have been standard practice for randonneurs since the beginning.

These days if you are near a printer, it is easy to download the cue sheet for a route made in RideWithGPS using the instructions here...
https://ridewithgps.com/help/create-customize-a-cuesheet

On my European double crossing in 2014, I only generally used the Eurovelo 6 route as a basic guide; many times -- particularly in Bulgaria, Romania and Serbia -- I made my own routes and sometimes those were cross-country or used farmer's access roads (with permission) or went far away from the standard route and its maps and signage. My cue sheets on that tour were much more basic than the RideWithGPS variety and were made with a pen and paper in my tent either the night before or morning of each day's ride and consisted of town names, turns, and notes on road designations. I found this especially helpful with Cyrillic place-names that I could not easily recognize. The GPS (I had a Garmin Oregon 400t, replaced after the trip with a 600t that has better reception and response on the touchscreen + plus Sygic maps and OpenStreetMaps on my then Samsung Galaxy S4 smartphone as a backup) was used only for when my cue sheets left me feeling short on directions or specifics. I would simply start it up at those times, get a sat-lock in a minute or so, check my position and alter my cue sheet notes as needed before shutting it off again.

In this way, I can greatly extend the battery life on my GPS. The cue sheet goes either in the map case of my Ortlieb handlebar bag or if it is dry, clipped to my handlebars on a CueClip, which I have always found reliable...
https://www.amazon.com/CueClip-Cue-Clip-Sheet-Holder/dp/B00D3VYBOE

Sometimes it is helpful to record your route as tracks for sharing later. If I equip my Garmin Oregon 600T with two fully charged Eneloop XX AA cells and keep screen brightness down, I can record 16-17 hours of GPS tracks before they go flat. This is usually adequate for most of my day rides but for longer 400km/24-hour rides, I do have to swap cells at some point or it won't track the full trip segment. I can combine tracks when I get home either by uploading the gpx data or by editing it at home on my PC.

As for battery charging, I use a combination of my SON dynohub and charger (now usually y Cycle2Charge), solar (1-2 Joos Orange solar panels, depending on how long I'll be away from mains power and where I'll be riding), two Sanyo Eneloop AA/AAA USB chargers (swapping between one and another depending on whether they are charging via solar or my dyno-charger) and a large capacity power bank I charge when I am at lodging or a restaurant (with permission). It really helps to take a multi-outlet USB charger for those occasions to avoid swapping charging devices in the middle of the night and I've also found it helpful to take a small adapter that converts a lamp socket to an electrical outlet. This avoids having to move furniture to reach an outlet that may be hidden by bedcovers and bureaus and such.

With these strategies, I've found I have enough power for my navigation needs with some left over for recharging my other gadget which I have chosen for their long battery life. Some (i.e. my LED headlamp) make more sense to run on Lithium batteries; one set of 4AAAs in my Black Diamond Storm lasted all 4 months of my tour and the light was still bright after. For other gadgets, Eneloops make more sense. My little Sony SRF-M37V weather radio typically runs for 65 hours on a single AAA battery, so it doesn't need to be replenished very often. My front white and rear red LED battery lights (used not to see with but to increase visibility to traffic in cities and tunnels and in urban areas) run for about 65 hours on two AA/AAA cells so again don't need recharging too often as usually leave them off except in high-traffic areas, preferring to run my dyno-powered LED lighting for general visibility and nighttime use. I have an older SteriPen that uses AA cells and I usually equip it with Eneloop XX cells and find I get at least 9 liters of purification without any problem and plenty of opportunity to solar or dyno-charge the spare batteries before needed. I also carry spare charged Eneloops of both standard and XX capacity in case of layover days away from mains power or continued rainy weather, nighttime runs, or slow uphills. My Th!nk Outside iGO Stowaway folding Bluetooth keyboard I use for production typing runs for about 65 hours on a couple AAA Eneloops.

My preferred smartphone these days is my older Samsung Galaxy Note 4, which has an ultra-power saving mode that really extends battery life by defaulting to a black-and-white display. Unless I am typing a lot and for a long time, the included stylus and "swipe" keyboard are nearly as fast and much quicker than twiddling my thumbs to type. The Note 4 uses removable user-replaceable batteries so I carry a couple of pre-charged spares each in a Samsung USB charging dock that is barely larger than the battery itself. When I am not actively using the phone I place it in "Airplane mode" to greatly extend battery life. Depending in any background apps, I lose about 2% of my battery charge every 12-14 hours, so I have plenty of standby. If I need longer standby, then I power the phone off completely and restart it when I need to use it.

I've had no problems with my chargers on fast downhills so far. I have three B&M e-Werks, two Cycle2Charges and one Tout Terrain The Plug 2+. All have been reliable. The only limitation has been their charging capacity sometimes not meeting demand for particularly power-hungry devices. The worst in this regard is The Plug, but that is because it is now a very old model. Later editions provide higher charge capacity. I have and sometimes still do run my GPS continuously powered by my dyno-charger and a pass-through battery, but I find I tend to prefer the less efficient course of using batteries I have charged separately and swap-in each day or as needed.

Of course, I take paper maps as backup and always include a compass with adjustable declination (my favorite for general use is a Suunto MD-11) and I often use these instead of the GPS for plotting cross-country courses in places where either heavy tree canopy, canyons, or mountain ranges block reliable access to a GPS signal.

Hope something in the above helps.

Best,

Dan.

mickeg

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Re: Pedal Cell
« Reply #8 on: April 21, 2022, 12:37:01 AM »
A dynohub is an alternator, simple as that.  Other dyno options like rim dynamos, same thing, they are just an alternator.

You spin an alternator faster than you planned, it puts out more power.  My vintage Triumph motorcycles worked that way, just an alternator with a permanent magnet, spin the engine faster and it put out more power.  They used a zener diode to drain of excess power at higher engine RPM.

So, if you go fast down a hill, you can be putting a lot of power into your USB charger.  I tried to make my own USB charger, finally gave up and bought a new off the shelf one because I kept blowing out my circuits.  I measured 33 volts out of my dynohub going down a shallow hill, not that steep and not that fast.

So, if your charger has a max speed rating, believe that it is there for a reason.

I do not recall what speed rating Sinewave has for thier units, but it is faster than I ever plan to go on a bicycle.  I bought their Revolution model for its good waterproofness.

hendrich

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Re: Pedal Cell
« Reply #9 on: April 21, 2022, 04:40:20 PM »
I have Schmidt son28 and a sinewave charger. It is a reliable and robust paring which is what I appreciate the most while on tour. This generates enough power for my needs without a significant drag. True, the rim dynamos generate more power, but 20-30 Watts over time is a significant drag. Something that was not mentioned in the cyclingabout review...I have read accounts of the rim dynamos slipping off the rim and into the spokes, because apparently, there is no fail-safe stop. I don't understand how that could not be engineer into the design. The ancient metal bottle generators were not allowed to do this.

Andre Jute

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Re: Pedal Cell
« Reply #10 on: April 22, 2022, 12:15:20 PM »
This:
Quote
20-30 Watts over time is a significant drag.

I have a USB port on the battery for my bike, the battery being quite big enough for the necessary assistance (rather than using it as an electric motorcycle) for a day’s ride with plenty left over for charging devices, but I’ve never used it. I just believe in redundant security in depth. Instead I prefer to carry a rechargeable power bank of the right size for whatever I will do on the day. Usually it is plugged into my phone and on from home, because on shorter rides I like my phone fully charged; the phone is in constant use monitoring my heart rate, which is limited by order of my cardiologist, and my heart rate  on any hill determines when the motor is cut in and then cut out again. The small power bank is big enough to recharge my iPhone SE (chosen for its sturdy aluminium shell) from dead to full three times, with some left over, and the bigger power bank can keep up reports (audio as well as visual) from the phone for eight hours. Either fits with the iPhone in a transparent weatherproof bag on the handlebar that was bought from my supermarket, Lidl, in one of their biannual bicycle weeks, and has lasted many years.

I did have a charger of my own construction to replenish devices from the SON hub dynamo but soon decided it was more of a danger to my health by blowing up the iPhone, which is sensitive to the regulation of the current fed to it, than a help, and repurposed the cheap parts from Aliexpress. I built it on a strip of ali angle which also offered mounting holes, and shrink wrapped the whole thing in piece of cable tidy I begged from an electrical contractor.

The Pedal Cell seems to me an accident waiting to happen when inevitably it slips into the spokes. That, as has been observed already, is not sound engineering, especially on a bicycle where fallback systems in depth have to be very carefully considered for whatever additional pedal power they will consume.

If that isn’t enough to condemn the Pedal Cell for me, the thing will demand replacement of the O-rings used for driving it (in the 21st century — pull the other one!) and on a  tyre-driven generator just any O-rings won’t do. I live in an agricultural centre with lots of hardware and machine shops, and have experience of spending a whole morning going from place to place to find an even approximately right O-ring. I’ve spent time and money, and a lot of the patient help from friends here and on other cycling conferences, rebuilding my bike as a low-tending-to-zero maintenance bicycle, so fragile O-rings are a personal no-no as well as unacceptable engineering.

But there’s more: I’m not the first in this thread to observe that a gennie on the tyre depends for its efficiency on a clean contact between the tyre and the generator’s drive wheelie, and all the more so when the drive wheelie is not toothed metal but an O-ring. More maintenance, probably daily in foul-condition riding. I confidently forecast that those of us who fitted a Hebie Chainglider won’t consider the Pedal Cell long before we turn it down. It seems to me the Pedal Cell is an implement for clean tarmac and fair weather, which cyclists on tour cannot guarantee.

And still more: Has Apple certified the output as copacetic for iPhones? Just asking, rhetorically: If Apple did, you can bet the makers of the Pedal Cell would shout it from the rooftops.

Lastly, the thing costs a niche-market, big margin price. I’m nobody’s unpaid beta-tester.  For such a high-rent tyre gennie, there is the known, proven top B&M tyre generator, which should be considered first (and probably last — it’s a very long time since I rode a bike without a hub dynamo), and other stalwarts of European four-seasons cycling also offer quality rim generators without the Pedal Cell’s engineering solecisms. Frankly, that so few cyclists today choose a tyre dynamo, when for the same money they can have a hub dynamo, is already an overwhelming argument. 

If the Pedal Cell won’t do for a credit card, short range, only in civilisation, rider like me, I think it needs stronger arguments in its favour than we’ve heard yet.

***
The Pedal Cell, like other bicycle charging schemes, is a bodge made necessary by those German legislators in the pockets of VW-Audi and Daimler-Benz who made the law that a bicycle’s power plant should deliver 3W at 15kph, which then became the universal de facto standard for bicycle lighting. Try this thought experiment of an alternative reality:

Suppose bicycle hubs were freed from ignorant, motorist-biased legislators. By now we would have hub dynamos, perhaps even tyre generators, that could produce 50W for the same drag as we now gain a miserable 3W. And manufacturers would already have developed much more robust regulation circuits so as not to blow out the car-strength lamps that this different direction of bicycle lighting plus the invention of the LED would have made possible. And it would all be pretty cheap because car parts could be used.

Pedal Cell’s makers would then have directed their energies into devising a splitter board with regulation and protection to suit all kinds of implements on the bike to use the extra potential not required for the lamps.

There’d be hardly any extra weight…

Ain’t gonna happen, of course.
« Last Edit: April 22, 2022, 06:02:32 PM by Andre Jute »

mickeg

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Re: Pedal Cell
« Reply #11 on: April 22, 2022, 02:44:08 PM »
..., the rim dynamos generate more power, but 20-30 Watts over time is a significant drag. ...

I have measured about 2.5 watts out of my Sinewave when doing exercise rides on flat ground.  I assume on mostly flat terrain that I would average closer to 2 when touring.  And in hilly terrain cut that in half or even less.

There is a German charger, I think called Forumsladder (spell?) that will put out much more power out of a dynohub.  I think the Cycle2Charge also puts out more than the Sinewave.

The electronics are all pretty efficient with almost no power losses.  But the dynohubs often have drag that is roughly double the output wattage from the charger.  I do not feel any drag from my dynohubs whether using lights or Sinewave or neither.  But I have heard people say that they can feel the drag on their hub if using the Forumsladder USB charger that has much higher output.

This is a decade old, but I suspect not much has changed, this is where I got my estimates for hub drag.
https://www.cyclinguk.org/sites/default/files/document/migrated/publication/feature-hub-dynamos.pdf

Assuming you do not read German, put this into google translate, this is pretty good on the chargers.  Also old, this publication has newer issues to that may have more info if interested.
https://fahrradzukunft.de/21/steckdose-unterwegs-4


JohnR

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Re: Pedal Cell
« Reply #12 on: April 22, 2022, 05:39:13 PM »
I wondered if a small solar panel might be an alternative but, as discussed here https://www.ukhillwalking.com/forums/gear/solar_chargers-614920, the output is very dependent on weather conditions. I therefore think it would be better to get one or more power banks. This 10,000mAh power bank weighs little more than 200g (less than half the weight of the Pedal Cell) https://www.amazon.co.uk/Anker-Ultra-Compact-High-Speed-VoltageBoost-Technology/dp/B07QXV6N1B and would fully charge a Garmin Edge 1030 (battery capacity 3300mAh) at least twice then grab every opportunity to charge the power bank and other accessories when near a power socket (a dual outlet USB charger and two cables would get two items charging at the same time).

mickeg

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Re: Pedal Cell
« Reply #13 on: April 22, 2022, 11:58:22 PM »
I am not sure what LEL is, but I usually suggest that people just be frugal with their power consumption if the trip is a week long or less and use powerbanks to charge up their devices.  When you get to weeks, carrying a solar panel or other power generating stuff can be much more useful.

A couple years ago I did a kayak trip, brought a couple small solar panels and a USB powered AA battery charger.  My GPS and headlight (for my head) were AA battery powered.  When I got home I decided to weight my charging gear and found that the weight of the panels and charger exceeded the weight of the batteries that they replaced.  Needless to say, no more solar panels on kayak trips for me.  The weight alone  was sufficient to convince me to just bring the charged up batteries I need instead of continuously re-aiming my panels as the sun moved, etc.

I have the dynohubs and charging gear, so I am going to use them.  But if I did not have that stuff, I would really consider cost and weight of good powerbanks.  And solar panels have improved a lot in the past decade while they have gotten a lot cheaper.  So those are clearly a good option now if you can expect to have the sunlight available for them.

Someone on this forum, his name does not come to me right now, lives in Canada, he uses a dynohub and Sinewave, charges up his single Anker powerbank while rolling during the day and then in evening charges everything from the power bank.  And that works well for him.

There is no single right way and there is no best way, length of trip, amount of sunlight, etc., these all factor in, as does cost and weight.  When traveling, my phone is almost always off or in airplane mode with no apps running, but if you are one that has to keep your phone on, you will need a lot more power than I do.