Hub Dynamos in Australia

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rifraf
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Re: Hub Dynamos in Australia

Postby rifraf » Fri Feb 28, 2014 4:58 pm

Hi,
I'm hoping for some recommendations and reasoning for a suitable item for my center-lock Son28.
This is used to hold the disk in place as opposed to the 6 bolts (of a 6 bolt version).
Basically a cassette lock I think (?).
I wont be utilising a disk as its my Extra-wheel trailer wheel but without the "lock" it appears there is an easy ingress to the bearings of water/muck etc. on the one side of the hub.
Thanks in advance :)
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Re: Hub Dynamos in Australia

Postby just4tehhalibut » Sat Mar 01, 2014 12:58 am

Maybe put a rubber in it Shimano-style?
Image

Or maybe this from SON and you can get it in red. Might be the better solution.
Image

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Re: Hub Dynamos in Australia

Postby Espresso_ » Sat Mar 01, 2014 8:35 am

What's the effect of rim size on these hubs?

I'm thinking of buying the SP PD8 for a 650b build I'm working on.

However if there are different hubs for different sized rims (ie the 20" version discussed in this thread), would the 650b vs 700c difference be problematic for the PD8 somehow?

I'll be using Hetres, so the overall wheel + tyre diameter won't be too different to a 700c with a 23mm tyre.

E

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Re: Hub Dynamos in Australia

Postby wqlava1 » Sat Mar 01, 2014 8:56 am

Espresso_ wrote:What's the effect of rim size on these hubs?

I'm thinking of buying the SP PD8 for a 650b build I'm working on.

However if there are different hubs for different sized rims (ie the 20" version discussed in this thread), would the 650b vs 700c difference be problematic for the PD8 somehow?

I'll be using Hetres, so the overall wheel + tyre diameter won't be too different to a 700c with a 23mm tyre.

E
Just use the P hub if you want more power at slower speeds, the S if you're happy with less power overall, and that max power ( voltage actually) coming in at higher revs, and PD-8x for slightly higher efficiency still. And choose brands other than SP if efficiency and weight are lower priorities.

I've got a couple of shimano Alfines, a SON Delux and an SV-8, and I happily ride my fixie with Alfine hub the most. But I'll use a PD-8x on the 650b I'm currently accumulating towards.

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Hub Dynamos in Australia

Postby RonK » Sat Mar 01, 2014 10:28 am

The effect is related to the rotation speed of the dynamo. You should use the 700c hub to get the correct charging output.
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Re: Hub Dynamos in Australia

Postby wqlava1 » Sat Mar 01, 2014 11:03 am

RonK wrote:The effect is related to the rotation speed of the dynamo. You should use the 700c hub to get the correct charging output.
Neither the P or S series SP hubs ( or their resp SON equivalents) are more "correct" for 700c. One just has a few less poles or windings and takes a few more rpm to produce max power. The lower power units are easier to pedal and in most cases with good lights produce quite enough to light your way. Just trade offs. We have no requirement to pass the STVZO regs here.

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Hub Dynamos in Australia

Postby RonK » Sat Mar 01, 2014 11:26 am

wqlava1 wrote:
RonK wrote:The effect is related to the rotation speed of the dynamo. You should use the 700c hub to get the correct charging output.
Neither the P or S series SP hubs ( or their resp SON equivalents) are more "correct" for 700c. One just has a few less poles or windings and takes a few more rpm to produce max power. The lower power units are easier to pedal and in most cases with good lights produce quite enough to light your way. Just trade offs. We have no requirement to pass the STVZO regs here.
Very few cycle tourists fit a dynamo hub just to "light your way". Most fit them to recharge the multitude of electronic devices tourists are wont to carry these days. Some devices will not even commence charging if sufficient output is not available. If (like most) you want to recharge electronics then a hub with higher output at lower speed is indeed the "correct" choice.

Given the choice, there is no rational reason for building a hub meant for 20" into a 700c or 650b wheel - in fact it would be short-sighted and just plain dumb.
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Re: Hub Dynamos in Australia

Postby wqlava1 » Sat Mar 01, 2014 3:06 pm

RonK wrote:
wqlava1 wrote:
RonK wrote:The effect is related to the rotation speed of the dynamo. You should use the 700c hub to get the correct charging output.
Neither the P or S series SP hubs ( or their resp SON equivalents) are more "correct" for 700c. One just has a few less poles or windings and takes a few more rpm to produce max power. The lower power units are easier to pedal and in most cases with good lights produce quite enough to light your way. Just trade offs. We have no requirement to pass the STVZO regs here.
Very few cycle tourists fit a dynamo hub just to "light your way". Most fit them to recharge the multitude of electronic devices tourists are wont to carry these days. Some devices will not even commence charging if sufficient output is not available. If (like most) you want to recharge electronics then a hub with higher output at lower speed is indeed the "correct" choice.

Given the choice, there is no rational reason for building a hub meant for 20" into a 700c or 650b wheel - in fact it would be short-sighted and just plain dumb.
Not all hub dynamo users are cycle tourists. If you wanted to go riding unloaded at night at a reasonable pace, it's quite sensible. And on one bike set up that way, I do, and so would many others.

I'd appreciate though if you left emotive phrases like " no rational reason", "short sighted" , and "just plain dumb" out and kept to the subject, and allow for the broad range of cycling interest that draw us together.

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Re: Hub Dynamos in Australia

Postby rifraf » Sat Mar 01, 2014 3:59 pm

just4tehhalibut wrote:Maybe put a rubber in it Shimano-style?
Image

Or maybe this from SON and you can get it in red. Might be the better solution.
Image
Thanks heaps for the thought.
I really just want a recommendation for a suitable center-lock ring (if thats the correct terminology).
I've gone of the route of plain polished alloy for my hubs in order not to stand out more than necessary due to my paranoia of my dynamo/IGH combo wheels so anodised accessories bring on a shudder though I appreciate their eye-candy worthyness. :D
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Re: Hub Dynamos in Australia

Postby rifraf » Sat Mar 01, 2014 4:12 pm

wqlava1 wrote: Not all hub dynamo users are cycle tourists. If you wanted to go riding unloaded at night at a reasonable pace, it's quite sensible. And on one bike set up that way, I do, and so would many others.
I've been using dynohubs for over 20 years now, starting with Sturmey Archer GH6's.
I began as a commuter needing to overcome a head injury induced memory issue making it impossible to get on with standard or indeed rechargeable batteries.
Simply put, I'd forget to purchase enough batteries or make sure my batteries were charged enough for my evening commute home.
The original dynamo hub system though extremely underpowered, were a god send to me.
Nowadays, I'd recommend anyone "consider" thinking forward enough to purchasing a model powerful enough to cater for potential future use to save yourself the expense of a new hub should your adventures ever go beyond needing just enough power to use your headlight/tail-light.
The ability to as well charge your phone and/or Garmin computer/gps truely makes utilisation of a dynohub something very useful.
I believe the initial price difference between hubs to be almost insignificant as is the difference in drag/effort to spin the varies hubs.
Good luck with any purchase decisions. :)
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Re: Hub Dynamos in Australia

Postby Espresso_ » Sat Mar 01, 2014 4:42 pm

While I've not cycle touring in mind, I'd probably just get an "overpowered" hub because there's not much reason not to.

Another stupid question: are certain lights made for certain hubs? Or can you get whatever light to work, assuming sufficient power output?

Do any hub-powered rear lights blink?

E

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Re: Hub Dynamos in Australia

Postby rifraf » Sat Mar 01, 2014 5:04 pm

Espresso_ wrote:While I've not cycle touring in mind, I'd probably just get an "overpowered" hub because there's not much reason not to.
I'd be inclined to follow that approach.
I'd even go so far as to recommend considering a disk braked hub.
Currently this appears about as future proofed as you can go.

My last bike was a 20 inch wheeled Moulton APB which I bought a non disk Sondelux.
I found after a tour that the Moulton wasnt suitable for my style of riding in Australia (as it couldnt carry enough water for extended journeys)
I replaced it with a larger wheeled bike which I then needed to buy a new dynamo hub for.
If I'd bought a future proofed hub in the first place at no real added expense for the initial purchase, I'd have only had to cough up for rims and spokes instead of a complete package.
Espresso_ wrote:Another stupid question: are certain lights made for certain hubs? Or can you get whatever light to work, assuming sufficient power output?

Do any hub-powered rear lights blink?

E
I ran initially my Edelux headlight with my original Sturmey Archer GH6 dynohub.

I'm not aware of any current lights being hub specific.
Some tail-lights are said to be headlight specific but thats about as esoteric as I've come across.

I believe their might be an issue with some lights not having over current protection.
Shimano hubs in particular have something you wire into the circuit to prevent overloading if memory serves.
You'd have to rely on another answer or research the topic yourself as utilising Son hubs/lights, I've no experience with this potential problem.
I can say from experience that whilst I've read some people think you cant mix a B&M Cyco or Edelux with a Supernova tail-light due to potential polarity issues, I've only used Edelux and Philips Lumiring tail-light and had no issue.
Hope some of this was useful.
Resources often offered:
http://www.peterwhitecycles.com/lightingsystems.htm" onclick="window.open(this.href);return false;
http://swhs.home.xs4all.nl/fiets/tests/ ... ex_en.html" onclick="window.open(this.href);return false;
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Re: Hub Dynamos in Australia

Postby Espresso_ » Sat Mar 01, 2014 5:29 pm

I'll be going a disc hub because I'll have discs on my bike. The future is here, in that respect.

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Hub Dynamos in Australia

Postby RonK » Sat Mar 01, 2014 6:14 pm

wqlava1 wrote:I'd appreciate though if you left emotive phrases like " no rational reason", "short sighted" , and "just plain dumb" out and kept to the subject, and allow for the broad range of cycling interest that draw us together.
Amusing that you choose to start an argument then complain when you get one.

There is nothing emotive about my comments - they are facts and I stand by them. The emotion has all come from you, but I guess that's the refuge of one with who cannot present a factual argument.

There is no dispute that an 8 Series S model will power an LED lamp (if you ride fast enough).

But given that apart from their output characteristics the S and P models of the 8 Series dynamo hubs are physically virtually identical and just a few dollars different in price, please feel free to explain:
- how it is rational to prefer a hub which produces less power at lower speeds
- why it is not short-sighted to select a hub which cannot effectively power a Garmin or iPhone, or charge an auxiliary battery
- why it is not dumb to take the time, effort and expense to build a wheel with an less-than-adequate hub dynamo.

Fire away.

Oh, and logical argument only please, we don't want emotion entering the discussion.
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Re: Hub Dynamos in Australia

Postby Blakeylonger » Sat Mar 01, 2014 10:35 pm

Espresso_ wrote:Another stupid question: are certain lights made for certain hubs? Or can you get whatever light to work, assuming sufficient power output?

Do any hub-powered rear lights blink?
supernova rear lights require DC input, only supernova headlights provide this.

all other rear lights expect AC input, DC input will be ok though.

none blink, because StVZO laws forbid it, besides, it's easier to judge distance from a solid light. Put reflectors on your pedals instead, much more visible.
RonK wrote:(if you ride fast enough).
Please. You would have to be going very slowly not to be able to power a current LED headlight off a 'small wheel' dynohub.
RonK wrote: - how it is rational to prefer a hub which produces less power at lower speeds
- why it is not short-sighted to select a hub which cannot effectively power a Garmin or iPhone, or charge an auxiliary battery
- why it is not dumb to take the time, effort and expense to build a wheel with an less-than-adequate hub dynamo.
Current LED headlights don't require 'large wheel' dynamos to produce sufficient current at riding speeds above walking pace, German StVZO testing even approves them for use when used as such.
Lighter weight hub & lower drag gives climbing gains and decreased rolling resistance, especially important in timed events such as PBP / Great Divide
Charging smartphones directly from hubs is inefficient due to the varying output of the hub and the expected clean input on smartphones, often you'll drain the battery more than charging it unless you're sustaining high (i.e. descending) speeds.

If you like touring on a rohloff equipped recumbent with four panniers and a rolltop bag and will be away from civilisation for extended periods, sure, go for maximum power generation. But not everyone needs that. Commuters don't need to charge their phones, long distance racers need to minimise losses.

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Re: Hub Dynamos in Australia

Postby wqlava1 » Sat Mar 01, 2014 11:32 pm

RonK wrote:
wqlava1 wrote:I'd appreciate though if you left emotive phrases like " no rational reason", "short sighted" , and "just plain dumb" out and kept to the subject, and allow for the broad range of cycling interest that draw us together.
Amusing that you choose to start an argument then complain when you get one.

There is nothing emotive about my comments - they are facts and I stand by them. The emotion has all come from you, but I guess that's the refuge of one with who cannot present a factual argument.

There is no dispute that an 8 Series S model will power an LED lamp (if you ride fast enough).

But given that apart from their output characteristics the S and P models of the 8 Series dynamo hubs are physically virtually identical and just a few dollars different in price, please feel free to explain:
- how it is rational to prefer a hub which produces less power at lower speeds
- why it is not short-sighted to select a hub which cannot effectively power a Garmin or iPhone, or charge an auxiliary battery
- why it is not dumb to take the time, effort and expense to build a wheel with an less-than-adequate hub dynamo.

Fire away.

Oh, and logical argument only please, we don't want emotion entering the discussion.
If as I said before I already have what you would think to be an adequate hub on the fixie I use around town, I already have another hub that you'd consider adequate on my excellent custom Aussie-framed touring bike, then I choose to save say only 2 watts by using an SP SV-8 hub on a road bike, why criticize? It's a much more easily quantifiable saving than updating from say one road groupset to the next, but we understand that when weight weenies talk about it. For me, the time to build up another wheel is just enjoyment, and the only cost of moving to another rim is twenty or thirty bucks of spokes. When my personal design brief doesn't include soldering up an extra circuit for powering my Garmin or my iPhone, it doesn't make me any less rational than you, it is no definitive indication of my shortsightedness ( I'm actually long sighted according to my optometrist :-). ), and I've been smart in building exactly what I need.

If I lacked the ability and tools to build wheels, if I knew that the domestic government would veto anything more than one bike, if I only went touring rather than any other cycling and depended on my electronic gear, I may have made different choices.

Others on this forum who come asking will all have different constraints and different interests. And as long as we explain the pros and cons they can make their own decisions.

I'm not saying any of this to argue with you. But there are valid reasons for using many parts that you or i wouldn't.

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Re: Hub Dynamos in Australia

Postby Tim » Sun Mar 02, 2014 9:19 am

Blakeylonger wrote:Charging smartphones directly from hubs is inefficient due to the varying output of the hub and the expected clean input on smartphones, often you'll drain the battery more than charging it unless you're sustaining high (i.e. descending) speeds.
Not quite right.
Most phones only require USB equivalent charging input ie. 5 Volts/0.5 Amps. Don't have to ride very fast to generate that sort of current, 2.5 Watts.
Apple tablets (and maybe phones, not sure) require 5 Volts/2 Amps. A whopping 10 Watts. I can generate that at about 15 KPH.
As far as varying/constant hub output is concerned all that is required is to wire-in a cache battery in between a rectifier (a simple, lightweight and relatively cheap devise such as an E Werk) and your phone.
The cache battery charges up (with sometimes varying input voltage levels) from the hub and the phone charges up with a constant voltage from the battery.
Alternately I just charge up a storage battery on the road and recharge devises later.
A very common and easy set-up practiced by myself and many other touring cyclists. The system works very well and does not flatten batteries.
Last edited by Tim on Sun Mar 02, 2014 10:10 am, edited 1 time in total.

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Re: Hub Dynamos in Australia

Postby il padrone » Sun Mar 02, 2014 10:09 am

Blakeylonger wrote:Lighter weight hub & lower drag gives climbing gains and decreased rolling resistance, especially important in timed events such as PBP / Great Divide
Guess what? Not everyone rides the PBP/Great Divide either. We are talking real lighting for real cyclists. Many cyclists use lights and find they may at times ride quite slowly up hills.
Blakeylonger wrote:Charging smartphones directly from hubs is inefficient due to the varying output of the hub and the expected clean input on smartphones, often you'll drain the battery more than charging it unless you're sustaining high (i.e. descending) speeds.
I don't even bother to try charging my smartphone while riding - the Samsung micro-USB lead just drops out at the first bump. If I did I would turn it off, of course. But on-tour, my solution is to charge a battery and use this at night to charge the phone - if I don't have a power point.
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Hub Dynamos in Australia

Postby RonK » Sun Mar 02, 2014 11:20 am

Blakeylonger wrote:Lighter weight hub & lower drag gives climbing gains and decreased rolling resistance, especially important in timed events such as PBP / Great Divide
The weight difference between an SV-8 and a PV-8 is 13 grams. That's at the hub, not the rim and will make zero difference to climbing performance.

The drag generated by a PV-8 is imperceptible. To argue that the even smaller difference in drag between the two models matters in any way is simply not credible.

Audax riders may be weight- concious, but they are rarely weight-weenies.

Finally, events like PBP and the Great Divide are not races. But it is quite common for Audax riders to use Garmin's and other electronic navigation aids in such events as PBP/Great Divide and they would want a dynamo hub that can power both their navigation device and their lights.
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Re: Hub Dynamos in Australia

Postby Blakeylonger » Sun Mar 02, 2014 4:09 pm

il padrone wrote: Guess what? Not everyone rides the PBP/Great Divide either. We are talking real lighting for real cyclists. Many cyclists use lights and find they may at times ride quite slowly up hills.
that.is.exactly.my.point. Ron seems to believe that everyone should have maximum power output to light up the road at walking pace and be able to charge a kitchen sink full of devices. Not everyone is Ron. Not everyone is Jesse Carlsson.

The standby light is so good on modern lights that even if you are delivering the mail up an unlit hill it'll kick in and provide enough light to see the 1m in front of your wandering 3km/hr wheel.

Future proofing is a fool's errand anyway, look at how far the hubs and lights have advanced and the prices dropped in the last 5 years alone.
il padrone wrote:I don't even bother to try charging my smartphone while riding - the Samsung micro-USB lead just drops out at the first bump. If I did I would turn it off, of course. But on-tour, my solution is to charge a battery and use this at night to charge the phone - if I don't have a power point.
Exactly, either charge a cache battery during the day, or charge your cache at mains voltage if you have access when you stop. Again, this is a remote touring problem, not a problem for the majority.
RonK wrote:The weight difference between an SV-8 and a PV-8 is 13 grams. That's at the hub, not the rim and will make zero difference to climbing performance.

The drag generated by a PV-8 is imperceptible. To argue that the even smaller difference in drag between the two models matters in any way is simply not credible.

Audax riders may be weight- concious, but they are rarely weight-weenies.

Finally, events like PBP and the Great Divide are not races. But it is quite common for Audax riders to use Garmin's and other electronic navigation aids in such events as PBP/Great Divide and they would want a dynamo hub that can power both their navigation device and their lights.
Welcome to Wrongtown Wrong-o.

Watts are watts and grams are grams, they all add up, especially over longer events. Marginal gains are marginal gains.
At 30km/hr the extra rider load is:
3N80: 8W
P8: 7W
SON delux: 6W
S8: 5.5W

Plug some figures into Analytical Cycling, yes 1.5W is nearly nothing if you're riding home from work, but over a 1200k brevet it's 10 minutes.

Climbing is a pure function of watts/kg. The Shimano is 490g, the SV-8 is 367g and the rest are in between. Up a 20km / 8% climb the weight and drag difference results in a ~1min gap, all else equal. (The drag is by far the bigger contributor here, the weight difference accounts for only ~7.5s)

The Tour Divide Race is most definitely a race. and just because brevets aren't races doesn't mean many people don't try to set the fastest times they can, and if you're outside the time cut by 1 second, you're a DNF.

you want higher current output for charging, bully for you.
other people want lower weight and drag, whether they're trying to win the transcontinental or set a new record for riding around the world, or just because, that's their prerogative.
still others just want affordable and reliable lights when they are rolling and DGAF about an extra 5W drag or 300g or the latest 90lux german wunderlicht.

don't tell them they're wrong for that and I won't tell you you're wrong. dandy horses for dandy courses.

Trying to charge a smartphone and many other devices directly is ineffective and will result in more loss of charge than gain unless you are at sustained high speed, especially iPhones. You're better off charging a high quality cache battery, like the Satechi, ideally at the powerpoint at the cafe you stopped at for lunch.

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Re: Hub Dynamos in Australia

Postby Tim » Sun Mar 02, 2014 4:42 pm

Blakeylonger wrote:Trying to charge a smartphone and many other devices directly is ineffective and will result in more loss of charge than gain unless you are at sustained high speed, especially iPhones. You're better off charging a high quality cache battery, like the Satechi, ideally at the powerpoint at the cafe you stopped at for lunch.
Funny that.
I can charge a phone or an Edge800, or AA and AAA batteries directly from my Shimano XT dynohub, no cache battery, just an EWerk to convert AC to DC and control maximum voltage and ampere levels. I average between 12 and 15 KPH on tour. I wouldn't call that sustained high speed. It is a very effective charging system and most definitely doesn't flatten any batteries.
Having said that though it is much simpler to just keep a 9Amp storage battery topped up throughout the day and recharge devises at night. If the storage battery becomes fully charged on the road I then start topping up devises as need be.
It works, it is effective and I have been doing it now for about the last two years on every tour.

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Re: Hub Dynamos in Australia

Postby il padrone » Sun Mar 02, 2014 4:59 pm

Blakeylonger wrote:Watts are watts and grams are grams, they all add up, especially over longer events. Marginal gains are marginal gains.
At 30km/hr the extra rider load is:
3N80: 8W
P8: 7W
SON delux: 6W
S8: 5.5W

Plug some figures into Analytical Cycling, yes 1.5W is nearly nothing if you're riding home from work, but over a 1200k brevet it's 10 minutes.
You are serious about that ? My understanding of Audax is that there is no race involved. On a 1200km brevet if 10 mins is critical to you then you're in trouble. Yes, I guess, if you're on the absolute time limit it's an issue, but otherwise.... nup! I ride far less than this and I'd guess my 80-100km day's tour will cause me to lose about 1 minute. Hmm..... guess I should be worried :wink:


Blakeylonger wrote:Climbing is a pure function of watts/kg. The Shimano is 490g, the SV-8 is 367g and the rest are in between. Up a 20km / 8% climb the weight and drag difference results in a ~1min gap, all else equal. (The drag is by far the bigger contributor here, the weight difference accounts for only ~7.5s)
The drag issue is so minimal it's ridiculous - unless you're doing a race. Shimano is a bit worse than the SON28 (I have no experience with the SP dynahubs) but friends of mine, and my own son, using the Shimano have no concerns riding the same pace and distances as I do with my SON28, or others with no dynahub.
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Re: Hub Dynamos in Australia

Postby wqlava1 » Sun Mar 02, 2014 5:35 pm

Blakeylonger wrote: Trying to charge a smartphone and many other devices directly is ineffective and will result in more loss of charge than gain unless you are at sustained high speed, especially iPhones. You're better off charging a high quality cache battery, like the Satechi, ideally at the powerpoint at the cafe you stopped at for lunch.
And the reason for this is very Australian, supporting the title of the thread. Smartphones are adaptive devices that turn their power level up when needed and down when close to a cell antenna. So in more populated places the power might be down around 100 or 250 milliwats, and out in the country it will try to communicate at full power - somewhere up around 2 or 3 watts. So in areas where you would have access to mains power the phone doesnt drain its battery all that fast. where you might need to charge the phone it will be draining its battery as fast as it can, just staying in contact with the nearest cell. And if you put it in airplane mode then the GPS functionality is off.

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Re: Hub Dynamos in Australia

Postby Blakeylonger » Mon Mar 03, 2014 9:45 am

Ugh,
Tim wrote:Funny that.
I can charge a phone or an Edge800, or AA and AAA batteries directly from my Shimano XT dynohub, no cache battery, just an EWerk
Funny that, I never said NO devices are able to be charged, I said SOME smartphones and similar, especially iphones, will not charge, and NO the ewerk will not charge an iphone unless you have a cache battery connected to it.

Even crotchety old Peter White spells it out:
Some devices, such as the 3GS iPhone, require a constant voltage from the charger. For devices like this, an intermediary or buffer cache battery must be used. The E-WERK will charge the battery, which then charges the device. The Busch & Müller cache battery can be charged by the E-WERK while simultaneously charging the device.
...
The E-WERK is compatible with most devices. One known exception is the Apple iPhone, 3GS and later models, which will only work if the charger has a constant 5 volt output. When the cyclist is starting and stopping, the output of the E-WERK will drop, and some devices including the iPhone will shut down. Also, some devices can't operate at all while they are charging. Busch & Müller makes a cache battery for use with the iPhone and other devices requiring constant voltage. This will act as a buffer between the E-WERK and the device in question. Use the E-WERK to charge the small cache battery, and the battery will then charge the iPhone or other device at a constant 5 volts. And all this can happen simultaneously. The iPhone 3G and earlier are not affected by this issue, so the cache battery is not required for the 3G and earlier iPhones.
And also SJS:
Please note : The Ewerk (even with Cache Battery) does not support Apple i devices with Software 4.3.3 older versions are fine
il padrone wrote: You are serious about that ? My understanding of Audax is that there is no race involved. On a 1200km brevet if 10 mins is critical to you then you're in trouble. Yes, I guess, if you're on the absolute time limit it's an issue, but otherwise.... nup! I ride far less than this and I'd guess my 80-100km day's tour will cause me to lose about 1 minute. Hmm..... guess I should be worried :wink:
again. I'm not disagreeing with you. if you are commuting, by all means run the slowest flatproof marathon tyres and charge your ipad while you ride in, it'll amount to less time loss than the traffic lights. If you are touring, you generally don't even need a fancy dyno headlight, because, who tours at night? I was giving examples of actual cases where watts and grams saved will have an effect on the outcome. Yes, they're small, but they add up over long events as described. So yes, on bike position, rolling resistance (hub drag, tyres etc), eating while riding and other factors will have a significant effect. Yes, tour divide is a race, yes, audax isn't a race, but your time is recorded on your brevet card and SOME PEOPLE like to aim for the / their fastest time.
il padrone wrote:The drag issue is so minimal it's ridiculous - unless you're doing a race. Shimano is a bit worse than the SON28 (I have no experience with the SP dynahubs) but friends of mine, and my own son, using the Shimano have no concerns riding the same pace and distances as I do with my SON28, or others with no dynahub.
Obviously your friends are stronger than you. ;)
wqlava1 wrote:So in areas where you would have access to mains power the phone doesnt drain its battery all that fast. where you might need to charge the phone it will be draining its battery as fast as it can, just staying in contact with the nearest cell. And if you put it in airplane mode then the GPS functionality is off.
There are many places in Australia with no cell service that have 240VAC. The Satechi is a 10000mAH battery, an iphone 5s has a 1570mAH battery. So you can charge it from zero SIX times while you are in the boondocks and away from any mains power.

There are plenty of phones with proper GPS (not just A-GPS), that can be enabled while the cell radio is disabled. My nexus 4 is one.

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rifraf
Posts: 3843
Joined: Fri Apr 15, 2011 5:55 pm
Location: Two Rocks, WA

Re: Hub Dynamos in Australia

Postby rifraf » Mon Mar 03, 2014 6:25 pm

Well some good news for me today.
Just looked at my bike24 package tracking and its looking like my 2nd E-werk is going to arrive tomorrow.
This is for my extrawheel trailer project designed as a charging platform as well as load bearer. :)
Surly Ogre, Extrawheel trailer.

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