Shimano Alfine DH-S701 1.5v Dynamo

[BrianP]

Building up a new front wheel dynamo charging system. Would like to run an LED front light and a USB charger connection for my Motorolo Moto G 4G phone.

This is the charger http://www.bike-discount.de/en/buy/alfi ... oCDNvw_wcB

Grateful for help with choosing best front light to match this item and USB connector system to charge the phone, so I can order at the same time.

Brian

[Brucey]

charger and a light from 1.5W? Not at the same time. Don't expect miracles from your charger either; even with the light off you will be pushing ~250mA tops into any battery, maybe less if the circuit isn't very efficient.

To spell it out, if you have a 1Ah battery it won't charge in less than four hours. A 3W generator will be about twice as fast to charge as a 1.5W generator.

cheers

[BrianP]

Simply thinking charge phone during the day, small use of lights at night for getting to pub and back kind if thing.

Not long dark commuting as I am retired.

Brian

[fatboy]

What lights are you supposed to use with these dynamos?

[BrianP]

Genesis have just been asking about people's experience with generators and the SP-PD8 seems to be working well. Price is also much closer to Alfine than the Son units.

https://www.facebook.com/GenesisBikesUK ... =1&theater

Brian

[BrianP]

Reading around this site and others the SP-PD8 looks very well regarded and probably my best bet in terms of quality, performance and value. Would you experienced guys agree.

Light to go with it looks like this one http://www.starbike.com/en/supernova-e3 ... oCyYnw_wcB

Which seems a very good price for such a product. Might be because light is on all the time, no switch!

Just need a USB connecting bit for this solution. Any offers?

Brian

[andrew_s]

For USB, the regular option would be the B+M USB-werk.
There are a number of cheap alternatives on eBay and Amazon. In general, if you use one of these you should avoid having it plugged into the hub whilst neither light nor USB power is in use (including after what's being charged fills up.

The neater alternative is to get front light and USB in one.
Best is the B+M Luxos U. This has the best beam available (certainly better then the Supernova), but is fairly large. It also has a cache battery so things don't go off charge when you stop (some items will stop charging and need a manual restart).
The Axa Luxx 70 plus, is cheaper, with a beam similar to the Supernova.
The Axa Nano 50 plus is cheaper and less bright, but still perfectly good for fairly fast riding in the dark countryside.

(links are just what came top in google)

When 1.5W dynohubs were approved, they were intended as a small, light and cheap option for town bikes that don't need anything wonderfully good.

[nickpaton]

Think you'll find there'll be very little useable current output from usb-werk when taking circuit conversion efficiencies into account - around 70% AFAIK. Doesn't leave a lot!
You'll need a 6v 3w hub dynamo if you also want to charge your phone etc.

Looking at Shimano's specs they state it's for led lights with no mention of charging electronics (via suitable "boxes").

[andrew_s]

Think you'll find there'll be very little useable current output from usb-werk

The OP has decided to get an SP PD-8, which is an entirely suitable hub.

[BrianP]

Thanks, tried to amend title but did not manage it.

The light with integrated USB connector seems to be down to about £100

http://www.bike24.com/1.php?content=8;n ... 411;mid=39

And the Axa Nano Plus for about half that http://www.bike-discount.de/en/buy/nano ... ight-26893

Brian

[WOOLIFERKINS]

Brian,
Don't forget if you have any warranty issue when buying from EU discounters you have to do it through the retailer you bought it from and they are notoriously poor at it.

[beardy]

I thought that I had seen the B&M light claiming a 1A USB and the AXA claiming only 500mA USB.

Looking at comments up thread it dawns on me that 6V and 3W only produces 500mA anyway.

I can not remember where I saw the 1A figure and 500mA figure. Possibly the 1A is short term relying on depleting the cache. Or did I imagine the different claims?

[interestedcp]

Reading around this site and others the SP-PD8 looks very well regarded and probably my best bet in terms of quality, performance and value. Would you experienced guys agree.

I don't agree with that. I think the main problem is that it can't serviced (like replacing it bearings), unless the entire wheel is taken apart. After the two year warranty expires, you will have to mail the hub directly to the factory in Taiwan in order to replace bearings. If you don't build your wheels yourself, this may add significant cost, since you have to pay for both taking the wheel apart and be assembled again.

Its performance is very similar to the the 3W Shimano Sport dynamo, yet it is much more expensive. It is lighter however, since it uses a aluminum axle instead of steel etc.

The bearing quality on the Shimano dynamo hubs is vastly superior in both shielding and quality to the SP hubs.

Light to go with it looks like this one http://www.starbike.com/en/supernova-e3 ... oCyYnw_wcB

Which seems a very good price for such a product. Might be because light is on all the time, no switch!

Just need a USB connecting bit for this solution. Any offers?

Haven't seen the beam pattern from this Supernova light, but generally speaking, the B&M lights have superior beam patterns because they also use indirect reflectors.
The 80 lux "Lumotec IQ Cyo Premium senso plus" is likely to be a better performer at half the price.
http://www.bike-discount.de/en/buy/lumo ... /wg_id-303

The Luxos U is almost the same price, but comes with inbuilt USB charger.
http://www.bike-discount.de/en/buy/lumo ... /wg_id-303

Regarding USB chargers; the idea is seemingly so simple, but there are several factors that are worth considering: Will the setup work when it is raining? Can you both charge and have usefull light on? Battery buffers may help some devices that don't like fluctuating power, but if the load on the battery is larger than the input, it will run dry, and probably refuse to charge until they have reached a certain capacity again. Some devices may not be usable while charging, or at least require changes in the setup to do so.
Last, there is the quality of the charger: some have surprising high parasitic drag, even when off. Some don't deal very well with high speed descents, some aren't weather proof, etc.

The best charger on the market in terms of electrical measurements, is the B&M E-Werk. Some figures can be seen here (in German though): http://fahrradzukunft.de/12/steckdose-unterwegs-2/

Presumably the B&M USB-Werk is of the same quality. It is simpler and probably what most people need since most devices will be USB these days. It has an inbuilt buffer battery with all the advantages and disadvantages that brings.

[WOOLIFERKINS]

The USB plug has gone from the current version of the Luxos and been replaced with the properly waterproof adaptor the ewerk uses so the only weather dubious connection is from cable to device. Just forget the 1.5v dynamo and buy a proper one. For their own FUBAR reasons Shimano have decided to opt out of the 20+ year industry dynamo standard, you're getting half the wigglies out of your dynamo so the rest of the worlds dynamo products won't work properly as there isn't the inbound grunt.

[edocaster]

I thought that I had seen the B&M light claiming a 1A USB and the AXA claiming only 500mA USB.

Looking at comments up thread it dawns on me that 6V and 3W only produces 500mA anyway.

I can not remember where I saw the 1A figure and 500mA figure. Possibly the 1A is short term relying on depleting the cache. Or did I imagine the different claims?

It is possible to get more than 3W if the dynamo voltage goes beyond 6V, and then a switching converter brings it down to 5V USB, resulting in more than 500mA current. But most off-the-shelf dynamo lights are made so as to stabilise at a standard 6V at low-ish speed, so I'm guessing they eschew higher power to stick to the German regs.

Here's another option on the cheap light+USB combined front: http://www.amazon.de/B%C3%BCchel-Fronts ... immerlicht

Reviewed here: http://fahrradbeleuchtung-info.de/testb ... icht-sport

The postage slightly kills the price, but it seems to perform as it should.