Dynamos - Hub or Bottle?

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Ontherivet77
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Joined: 3 Jun 2009, 3:20pm
Location: Lancashire

Dynamos - Hub or Bottle?

Postby Ontherivet77 » 23 Jan 2019, 8:37am

After a couple of front light failures while commuting I'm considering the dynamo option.
I've been looking at this :
https://www.sjscycles.co.uk/dynamos/axa ... namo-left/

and these:
https://www.sjscycles.co.uk/wheelswheel ... ub-silver/

Although, I accept/presume that hub dynamos are much better than bottles are they worth 10 times the difference.
Also, what is your experience with drag and weight with both these options?
Many thanks in advance.

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Patrickpioneer
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Location: Brynteg

Re: Dynamos - Hub or Bottle?

Postby Patrickpioneer » 23 Jan 2019, 8:43am

if your using a hack bike for commuting bung a bottle dynamo on it, if its a good bike and has value then get a hub dynamo.
Pat

Mike_Ayling
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Joined: 25 Sep 2017, 3:02am
Location: Melbourne Australia

Re: Dynamos - Hub or Bottle?

Postby Mike_Ayling » 23 Jan 2019, 8:49am

Last time I used a bottle dynamo was about sixty years ago and at that time they provided plenty of drag as well as plenty of light if you were riding fast enough!

I am told that most people cannot detect if their hub dynamos are switched on or not and most riders never turn them off, running lights night and day, i.e there is very little drag.

Mike

pwa
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Re: Dynamos - Hub or Bottle?

Postby pwa » 23 Jan 2019, 8:51am

Bottle dynamos are better when the dynamo is not being used. No drag. But I gave up using one about twenty years ago because it was very unreliable in the rain. It would slip on the tyre, meaning no light. Getting them not to do that seemed to be a black art. And in those days you were limited in tyre choice. Use the wrong tyre and you risked sidewall damage.

If you want a reliable dynamo for commuting, hub is the way to go. It will drag a little even when not in use, but when you flick the switch you will get light. I find, though, that on a slow climb the light flickers and isn't so bright, which is annoying if you are used to consistent light. I use a battery light too as back-up. And I can feel the drag. I feel the bike slow down quicker when I stop pedalling than it does with no dynamo.

With regard to battery lights, if you are willing to dig deep in your wallet Exposure are about to release a range of lights with dipped beams that put the light on the road and not in the face of oncoming traffic. I find Exposure very reliable but their previous offerings have not been so road specific. That would be my choice for commuting.

Greystoke
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Location: Lincolnshire

Re: Dynamos - Hub or Bottle?

Postby Greystoke » 23 Jan 2019, 9:15am

I've successfully used bottle dynamos for years and fitted a dynamo hub for this winters commute. It's much better, the bottle dynamo would slip in the wet as I overpower mine but the hub provides good power whatever the weather.

robc02
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Location: Stafford

Re: Dynamos - Hub or Bottle?

Postby robc02 » 23 Jan 2019, 9:36am

B&M do an all weather wire roller for their bottle dynamos:

https://www.sjscycles.co.uk/dynamos/busch-muller-dymotec-all-weather-roller-cap-wire-brush-type/

The dynamo wheel in the OP is a top quality item with a price tag to match. Shimano do a range of dynamo hubs starting at around £30. Here are a couple heavily discounted to around £20:

https://www.sjscycles.co.uk/dynamos/shimano-dh2n35qr-6v-24w-dynamo-front-hub-black-36-hole/
https://www.sjscycles.co.uk/dynamos/shimano-dh3d37qr-6v-30w-quick-release-centre-lock-disc-dynamo-front-hub-silver-36-hole/

You would have to build them into a wheel, of course, but it needn't be as expensive as the example in the OP. It is a price / quality / performance compromise, as usual, but there are very many happy users of the cheapest Shimano dynamo hubs.

pwa
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Joined: 2 Oct 2011, 8:55pm

Re: Dynamos - Hub or Bottle?

Postby pwa » 23 Jan 2019, 9:40am

I'd not use and Open pro rim for commuting. I would go through one in one winter.

Greystoke
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Location: Lincolnshire

Re: Dynamos - Hub or Bottle?

Postby Greystoke » 23 Jan 2019, 9:41am

Look at decathlon, they do complete 700c dynohub wheels for the price of a shimano dynohub

Brucey
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Re: Dynamos - Hub or Bottle?

Postby Brucey » 23 Jan 2019, 9:49am

bottle dynamos are almost extinct and the reason is that they are in nearly every respect inferior to a hub dynamo setup. You don't have to spend £250 on a posh hub dynamo wheel to find out if a hub dynamo will suit you or not; you can buy workable wheels from about £30 (eg in Decathlon).

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Bmblbzzz
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Re: Dynamos - Hub or Bottle?

Postby Bmblbzzz » 23 Jan 2019, 9:50am

Greystoke wrote:Look at decathlon, they do complete 700c dynohub wheels for the price of a shimano dynohub

Word! https://www.decathlon.co.uk/26-hybrid-f ... 31687.html
But they only seem to have 26" wheels. Nevertheless, you can get a Shimano hub dynamo for about £30 and build a wheel on that with whatever rim you want.

Bmblbzzz
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Re: Dynamos - Hub or Bottle?

Postby Bmblbzzz » 23 Jan 2019, 9:52am


tod28
Posts: 69
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Re: Dynamos - Hub or Bottle?

Postby tod28 » 23 Jan 2019, 10:28am



That's for a small wheel jobbie (74 mm OLN)

Decathlon have 28" dynamo wheels for ~£30 https://www.decathlon.co.uk/28-front-hybrid-dynamo-wheel-id_8133890.html

slowster
Posts: 936
Joined: 7 Jul 2017, 10:37am

Re: Dynamos - Hub or Bottle?

Postby slowster » 23 Jan 2019, 10:29am

Bmblbzzz wrote:
Greystoke wrote:Look at decathlon, they do complete 700c dynohub wheels for the price of a shimano dynohub

Word! https://www.decathlon.co.uk/26-hybrid-f ... 31687.html
But they only seem to have 26" wheels. Nevertheless, you can get a Shimano hub dynamo for about £30 and build a wheel on that with whatever rim you want.

Link to 700C (28") version - https://www.decathlon.co.uk/28-front-hybrid-dynamo-wheel-id_8133890.html.

You will also need a connector box. These are normally £4 at Decathlon but difficult to find on their website and I cannot locate it at the moment*, but only £2 at Spa and SJS, e.g. https://www.spacycles.co.uk/m2b0s133p1914/SHIMANO-Dynamo-connectors. If you can find it on Decathlon's website it might make sense to buy from them because it takes the order over the free postage threshold with the wheel.

* Edit - found the little swine https://www.decathlon.co.uk/connector-cap-and-cover-id_8078831.html. It's £3.50, not £4.
Last edited by slowster on 23 Jan 2019, 10:34am, edited 2 times in total.

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Dynamos - Hub or Bottle?

Postby Brucey » 23 Jan 2019, 10:30am

decathlon 700C hub dynamo wheel £29.99 is listed as 28"

https://www.decathlon.co.uk/28-front-hybrid-dynamo-wheel-id_8133890.html

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

PH
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Re: Dynamos - Hub or Bottle?

Postby PH » 23 Jan 2019, 10:38am

It's all been said so I'll just +1 it. I have three and don't notice the weight and drag, I know several people who bought hub dynamo wheels with the intention of swapping Summer/Winter, but none who have bothered once they realise the difference is so small.
IMO the only reason to choose a bottle dynamo is if for some reason you couldn't fit a hub version.