Author Topic: Dynahubs  (Read 10541 times)

energyman

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Dynahubs
« on: November 21, 2016, 07:13:21 pm »
I have noticed that some dynahubs are rated at 1.5 watts.  Checking this with Rose.de I was informed that this is OK to run both front & rear lighting.
Now I am confused as I know LED lighting is low powered and bright but 1.5 watts can this be enough to run a reasonably bright light ?
Reason I'm asking is that my dear wife cycles to the next village to her keep fit classes and needs a reasonable light and her present light eats batteries.


mickeg

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Re: Dynahubs
« Reply #1 on: November 21, 2016, 07:37:27 pm »
I bought my hub primarily to use for charging batteries for electronic devices and for that I wanted as much power as I could get.  But if the hub will never be used for anything other than lighting, maybe a 1.5 watt hub would be enough?

I think the Velological unit is 1.5 watts. 
http://www.velogical-engineering.com/rim-dynamo-en-1

If so, you could use your existing wheel and avoid the cost of spokes to build up a new wheel if you go for that option.  I have never seen the Velological unit, but it looks intriguing from what I see on my computer screen.

But if you might want it to charge electronic devices, I think you want the 3 watt hub.

Danneaux

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Re: Dynahubs
« Reply #2 on: November 21, 2016, 08:02:25 pm »
Quote
I have never seen the Velological unit...
I saw my first one in person on the local bike path last week. Heard it first, as the thing was surprisingly noisy, much like my old Sanyo Dynapower bottom bracket (actually chainstay mounted) dynamo.

The Velological rim-drive dynamo comes in three versions, Sport, Trekking, and Special. Each varies in the amount of drag and the speed at which full power is produced. See: http://www.velogical-engineering.com/rim-dynamo-en-1

Best,

Dan.

jags

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Re: Dynahubs
« Reply #3 on: November 21, 2016, 08:03:02 pm »
that looks amazing but expensive. :'(

DAntrim

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Re: Dynahubs
« Reply #4 on: November 21, 2016, 10:07:24 pm »
I have the SP - PD8 dynamo, built into a wheel last year from SJS, and have combined this with the B&M Luxos B front and Toplight Line plus rear. Having used this setup over the past year for my daily commute, there has never been an issue with dim lights front or rear, if anything the the spread of light from the front is better than most battery lights I've used in the past. Add in the ability to charge devices while away, its the best investment made - after the bike ofc.

Peter White Cycles has an article showing spread patterns of various dynamo lights.....
http://www.peterwhitecycles.com/b&m-hl.php

Though I cannot charge and run lights at the same time - always one downfall.

Carlos





mickeg

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Re: Dynahubs
« Reply #5 on: November 21, 2016, 10:38:39 pm »
Quote
I have never seen the Velological unit...
I saw my first one in person on the local bike path last week. Heard it first, as the thing was surprisingly noisy, ...

If I knew that, I would not have suggested it.  At night in the dark I really hate a noisy bike.

I have a vintage Union sidewall generator (alternator) on my errand bike.  It is nice for a mile or two at a time (it is an errand bike), but any more distance and I would go nutty from the noise.

The SP PV-8 on my Nomad is trouble free and silent.  Some people have complained of vibration in the handlebars when they use a dynohub.  I have never felt any vibration on my Nomad, I suspect that a lighter duty fork might transmit more vibration than the heavy fork on my Nomad.

jags

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Re: Dynahubs
« Reply #6 on: November 21, 2016, 10:51:27 pm »
i had  a Shimano dyno hub on the sherpa  never had one second bother with it ,wasn't expensive either for the wheel stayed perfectly true for the time i had it.
i had front and rear lights  worked great never charged anything tho.

jags.

andrew_s

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Re: Dynahubs
« Reply #7 on: December 15, 2016, 03:46:24 pm »
Yes, a 1.5W hub used with LED lighting front and rear will give light that is OK (i.e. better than was available before LED front lights).
LED light brightness is more or less linear with power, so half the power = half the light out. On the other hand, the response of the eye is non-linear, so half the light only looks a bit less bright.

mickeg

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Re: Dynahubs
« Reply #8 on: December 15, 2016, 09:34:41 pm »
Yes, a 1.5W hub used with LED lighting front and rear will give light that is OK (i.e. better than was available before LED front lights).
LED light brightness is more or less linear with power, so half the power = half the light out. On the other hand, the response of the eye is non-linear, so half the light only looks a bit less bright.

Maybe they are near linear at low speed but not at higher speeds where the hub can put out more power than the lights can use.  With my 3 watt hub, I get about the same amount of light at 10 mph (~15km/hour) as I get at 20 mph (~30 km/hour).

jags

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Re: Dynahubs
« Reply #9 on: December 15, 2016, 10:55:48 pm »
so whats the best set up for lights and charging batteries,
rim spokes  dynamo  battery pk  photos would be a big help for my tiny brain . ::)

anto.

Danneaux

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Re: Dynahubs
« Reply #10 on: December 16, 2016, 03:06:34 am »
Anto,

You can check out photos of my setup in Danneaux's Nomad gallery or Danneaux's Sherpa gallery, but mine is just is one of many configurations that will work. I actually have several different setups on various bikes and they all work fine for my needs.

At its most simple, the basic setup works like this:

               //==========headlight=====taillight
Dynohub
               \\==========charging unit===buffer battery===gadget

When nothing is being charged, you can choose to have your headlight switched on...or off.

When something is being charged, it is best to turn your headlight off so your gadget can receive the maximum charge.

I have found I can charge some gadgets while my light is operating, but not others. It depends on how much juice is required. Best to turn off the lights when charging. Otherwise, charging will take longer or may not happen at all.

To hook it up, the easiest way is to use piggyback connectors at the hub. The two light wires plug into the first set of connectors, and the two taillight wires plug into the headlight. The two charger wires plug into the second set of piggyback connectors at the hub. It doesn't matter which goes where.

If you are simply charging batteries rather than powering a gadget, you probably don't need a buffer battery. If you need to keep your gadget operating while going slowly or stopped, then the buffer battery will keep it from turning off at those times (and you won't have to remember to turn it back on each time you restart).

Another reason to use a buffer battery is it can allow you to charge a gadget that would otherwise draw too much power to charge directly. Charge the buffer battery, then either use it to "pass through" electricity to power your gadget or...charge the buffer battery and use it later (perhaps while in camp) to charge your device. Next day, your cycling will recharge the buffer battery and off you go again.

This is a very simple explanation, but the diagram above covers all the basics.

The hookup is easy; the difficult part is determining if a specific charging setup will indeed charge or directly power your device. Output and requirements differ, so it can take some fussing to get a setup that will reliably charge a given gadget. This can be where some research, careful selection, and even trial and error come into play.

As for hardware, it is also pretty straightforward:
• A complete pre-built front wheel with a dynohub /or/ dynohub, rim, and spokes...just like you would with a standard front wheel. Only the hub differs.
• Headlight
• Taillight (optional, you can use a battery-powered LED blinky)
• Charging unit
• Two-conductor wire
• Some crimp-on spade connectors in the proper size.
• Some piggyback spade connectors for the hub connection.
• Some way to secure the loose wires to the bike (cable ties, tape, heat-shrink tubing, etc).
• Buffer battery (optional depending on requirements).
• USB charging cord appropriate to your gadget (shorter is better).

Hope this helps.

All the best,

Dan.
« Last Edit: December 16, 2016, 03:16:55 am by Danneaux »

David Simpson

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Re: Dynahubs
« Reply #11 on: December 16, 2016, 03:47:06 am »
For a buffer battery, I use one of these:
https://patriotmemory.com/product/fuel-active-mobile-rechargeable-battery-2600-mah-with-3-stage-led-flashlight/

- Very compact
- 2600mAh battery
- Allows pass-through charging (charge your device while charging the buffer battery)  <-- Necessary in order to use as a buffer battery.
- Built-in LED flashlight is really handy. Makes a great emergency flashlight for your toolbox.
- Quite inexpensive (US$10)
- The output is 1A, not the 2A that a larger device (iPad) would require. Works great with my Garmin Oregon GPS.

I found that they gave me free shipping when I ordered at least 3 of them. They ship from California, and I'm in Canada. It appears that the free shipping is only within US and Canada.

Disclaimer: I have no commercial interest in them. I'm just a satisfied customer.

- DaveS
« Last Edit: December 16, 2016, 04:50:42 pm by David Simpson »

mickeg

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Re: Dynahubs
« Reply #12 on: December 16, 2016, 05:04:04 am »
so whats the best set up for lights and charging batteries,
rim spokes  dynamo  battery pk  photos would be a big help for my tiny brain . ::)

anto.

If you just bought a new bike and therefore already bought a front wheel, a dynohub at this time would not be cheap.  If you keep your existing wheel, you need new dynohub, spokes, rim, rim tape, possibly labor charge to put it together.  If you rob the rim from your existing wheel, all you save is the cost of a rim but you lose the use of a complete wheel.  I use the SP PV8 dynohub, bought it in spring 2013 and it has been trouble free.

I use the Sinewave Revolution USB charger when touring, but for use around home I use a AXA Luxx 70 Plus headlamp that also has a USB charging port.  I was unimpressed with the AXA waterproofing, that is why I bought the Sinewave for touring.  Sinewave is made and sold in USA, so I have no idea what the cost would be in Europe.

I use a battery powered taillight.

I described the AXA Luxx 70 Plus at this link.
http://thorncyclesforum.co.uk/index.php?topic=11153.0

Neither the Sinewave or AXA Luxx 70 Plus has a cache battery to keep the power up to the USB when you stop or go slow.  Some devices protest when you slow down because if the device can't draw as much power as it wants, it quits trying to charge.

leftpoole

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Re: Dynahubs
« Reply #13 on: December 16, 2016, 09:39:49 am »
Hello,
These hubs are called 'Dynamo hubs'.!
John (who likes correct pronunciation)

energyman

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Re: Dynahubs
« Reply #14 on: December 16, 2016, 12:26:43 pm »
..... and of course they are alternators and not dynamos (well mine is anyway)