Cycling UK Forum

Just a request for some recommendations for an inexpensive dynamo setup for occasional use. The owner isn't awfully fussed about aesthetics but it's an old Raleigh 3 spd with a fair amount of chrome so it would be good if we could find lights with a silver colour rather than a big chunk of black plastic. A standlight might be advantageous (though by no means essential), but don't need anything fancy like switches or auto functions (largely superfluous with a sidewall dyno anyway).

Thanks in advance

trouble is cheap sidewall dynos only work in the dry, what you want is a reliable dyno that will always work even if it rains, other wise you will stop using it? You see many old bikes with the bottle dyno just as an attachment that hasnt been used for a long time with the wires to it orphaned. There is only one that can be guaranteed to work ( as you can get a wire roller ), which is the expensive in the UK ( but not Germany ) B&M Dymotec 6 ( UK price about £50, Germany £25 )

You can get very cheap hub dynos now so that might be the way to go I think. Can be got for about £30 incl the wheel and you dont have the real trouble of attaching the bottle dyno and keeping it aligned to the wheel. An Axa Pico30 front light is very small and discrete and dont cost much.

If the dyno is only for occasional use maybe just some good battery lights?

Thanks for the reply. The budget can certainly stretch to the B&M dyno if it's markedly better. I just said inexpensive to avoid umpteen posts recommending dynohub wheelbuilds and premium headlights which make sense for enthusiasts but would be overkill here. Aside from the cost of a dynowheel build the rims are 451mm so probably not stocked by many wheel builders. Attaching a bottle dynamo shouldn't be an issue because one was fitted originally.

I am looking into dynamo options because the owner is getting older. She has forgotten to replace batteries (or the lights themselves back on the bike) and ended up cycling home without lights several times. A dynamo seemed a simple solution.

its only better as you can get an optional wire brush type roller that will work under all conditions where as rubber ones will slip, maybe. There are cheaper Axa ones which are just as good electronically, but some one will have to recommend them. If your friend dont go out when it is raining or when water will splash onto the wheels then one of those might do.

The trouble is fixing these things to the fork as dont assume any old dyno will fit on any old fork. they all have different length "arms". The bracket on my fork was too short so had to use an extension you cant get now that bolts onto the brake caliper bolt

click pics for bigger ones



You can see the small fork bracket that I cant use & the loop that attaches to the brake caliper bolt - thats a common place for these to attach to.



I am also not using the wire roller as I rarely go out in the rain.



If your do decide to get a bottle dyno system look at eg Rose Cycles in Germany as you can save a lot of money, even when you factor in postage of about £7#

I've had this bottle dyno for 10+ years and only once had to lube the spring action that holds it onto the wheel.

mercalia wrote:
The trouble is fixing these things to the fork as dont assume any old dyno will fit on any old fork. they all have different length "arms". The bracket on my fork was too short so had to use an extension you cant get now that bolts onto the brake caliper bolt

You can still get these and they work well with a Dymotec on canti or V brake posts.

mercalia wrote:... had to use an extension you cant get now that bolts onto the brake caliper bolt ...

Zinkens Dynashoe if you want to place a wanted ad or search ebay.

In fact I use these dynamos on my road bikes as a first choice. They are undoubtedly the most efficient commonly found dynamos you can use, in every way, except they use a minute fraction more energy to drive, which when you think about it is the thing nearly everyone does with them the least!
They have an adjustment for their pressure onto the tyre. Apart from finding it neccessary to stop before turning them on in wet weather I have had no trouble with them slipping when wet, just using their normal drive cap. One needs to be very carefull to arrange their axis perpendicular to the axle centre, which can be fiddly. Once this is accomplished I have found them to offer years of trouble free life.
The normal range of dynamo lights can be coupled to them and if as others have suggested you purchase them from European suppliers they are far cheaper and are listed on Rose Bikes pages as "components" not accesories. Also you will find unless they expressly say otherwise all the bicycle lights they have will comply with all the European bicycle lighting specifications (and thus here).

Here the very cheap ( from Rose Cycles ) Pico30 - is a tiny light with a great deal of light, good enough for country roads at modest speed

In fact the one I have is over kill as it has a switch for hub dynos, but Rose Cycles dont stock the basic and very cheap one without - the switched one has an advantage as it has a captive wire to go to the rear light ( to switch it off ) so only need one wire to the bottle dyno


compare size to the frame tubes

Rear B&M carrier "standlight" which keeps on for 1 minute after stopped





Here is a link to the other bottle dyno worth considering that is REALLY cheap

(right side of fork)
https://www.rosebikes.com/article/axa-hr-traction-dynamo/aid:50395

or

(left side of fork)
https://www.rosebikes.com/article/axa-hr-traction-dynamo-50397/aid:50399

I have never used one so can't comment on how well it sticks to the tyre wall in the rain

NOTE YOU CAN GET BOTTLE DYNOS IN LEFT OR RIGHT POSITION OF THE FORK AS THE 2 ADVERTS FOR THE AXA SHOWS

I've used AXA HR dynamos for years (but as with all sidewall dynamos you need a dynamo track on your tyre).

I always buy dynamo stuff from German companies (bike24 is my favourite as they only charge 6 euros for postage) as it's much cheaper

fatboy wrote:I've used AXA HR dynamos for years (but as with all sidewall dynamos you need a dynamo track on your tyre).

I am still using an Axa HR. A good dynamo track with radial grooves means it doesnt slip in the wet. For some reason, Schwalbe seemed to be phasing it out recently and putting some nice-looking but less-effective diagonally-grooved track on their tyres.

I prefer mounting the dynamo on the rear wheel as the noise is less objectionable to my ears.

What about a classic chrome SA dynohub to match the bike.....
Apparently they will drive LED lamps OK (the higher wattage ones at reduced output).

Seem to be some good suggestions and advice here. As others have said they are available for Left or Right mounting. Maybe worth knowing that this does not mean to the Left or Right of the bike but mounted with the fork or stay to the left or right of the dynamo.
As mentioned above, I also prefer them mounted on the rear stay. This stops you from being sprayed with the fine mist that can come off them when using them in the rain. I also find that mounted behind the rear stay they fit comfortably under my rear pannier rack, this has the dual advantage of protecting them when leaning the bike against things and also makes them more unobtrusive, particularly when mounted on the chain side - which is the side I normally lean the bike. I find my panniers fit over them with no problem although this does make it a little fiddly to turn on.
The gentle magnetic whine- which occurs when magnetic fields cut across each other and due to the speed that these dynamos turn is audible (if you work it out you will find that a hub dynamo turns at only about 350Rpm at 20Mph)- helps Badgers, Foxes and other wildlife to know my position better, when they are conffuddled by the light. I find it also has the advantage of making pedestrians look round to see what the unaccustomed sound is, very useful on shared use paths.
I have heard good things of the AXA dynamos as well, although I have never used them.

Giles Pargiter wrote:Seem to be some good suggestions and advice here. As others have said they are available for Left or Right mounting. Maybe worth knowing that this does not mean to the Left or Right of the bike but mounted with the fork or stay to the left or right of the dynamo.

oh thats potentially confusing & hard to understand & not sure right? If you put the dyno on the front fork if you get a left one it goes on the left fork. I just checked my spare one - marked left on the box and goes on the left fork. By your thinking I should need a right one on the left fork? any way confusing.

The one problem with mounting on the rear stays is the mudguard - I cant as the tall Marathon 1.75" tyres I have too close to the rear muguard and the dyno track obscured , obviously no such probem with the front

Axa have some real cheap dynos also

https://www.bike24.com/1.php?content=13&search=dynamo

rather than the one mentioned above.