Dynamo Lights

[Insert standard UTFS disclaimer]

Loved the way my girlfriends bike always had a front light. Plus it worked well.

Seriously tempted to build a front wheel with a dynohub - like this Shimano Nexus one for £30ish

plus this bush & Muller retro lamp for around £26ish

Is it just a waist of money?

Does anyone use dynamo's?

Hubs front or rear, bottles, relights?

What are ppls experience?

The hubs range wildly in price, is it simply a case of you get what you pay for, or is there a product that represents an especially good balance? - like an on-one rear hub?

I've been wanting a dynohub for about 2 years, I just can't quite justify the expense, I like the idea of a dynohub on a road bike as you never have to worry about hte joice running out.

schmidt son hub are the best
then
shimano dynohub dh3n80
then
shimano dynohub dh3n70
then the nexus

there is a comparison on the web somewhere although the shimano one tested is meant to be the nexus one the newer shimanos are meant to have better internals.

Newer comparison here.

Loads of diffrent headlights out there LED ones are meant to be the best loads of home made jobs too. I think I'd personally go for one of the shimanos the 70 one at £50 is not too bad.

Cheers.

I thought that all modern dynohubs would run on magnets, but from your link they seem to still provide resitance?

• anyone got experience of the drag diff on a dynohub?
  
  

Its not something I'd want to spend too much on... my rough estimate is even on an mavic open sport and the Nexus it still comes in at £60ish.

hummm... worth it or not?

They all run on magnets, it's electro magnetic conduction that is how electric is made everywhere via mechanical means. Of course they will create extra resistance, you can't get something for nothing.

Worth it depends on how much night riding you do I guess.

If you want light without having to remember about it, there's no question - dynohubs are the way to go. I think they're worth the money without any doubt at all but you're right, you can spend and spend on them.

I went for a Schmidt a long time ago, and it's great - you don't notice it's on. The drag it produces is supposed to be equivalent to something like a seven foot climb over a mile of distance. The Shimanos are more, but even there it's not a lot. (Oh, yes, they all use magnets: that's what produces the drag. Even the oldest Sturmey dynohubs used magnets.)

The older Shimano (Nexus; NX-30) had a poor reputation for drag, but having built a wheel for my ex with one even that seemed to be completely acceptable - the newer ones (Alfine, DH-N70/1/2 and 80) are supposed to be better. There seems to be a new one on the market from Novatec too but apart from following the links above I know very little about that.

The cheapest way to try it at the moment is probably Spa Cycles, who are doing a Novatec-based wheel and light for about £60. Some of the German websites (www.boc24.de and www.rose.de for example) sometimes have dirt-cheap dynohub wheels as well, and they also tend to have good prices on the better hubs.

I'd say the best price point is probably the mid-to-expensive Shimano hubs at probably £60-£80. Once it's built into a wheel, the cost difference over a cheapie isn't so much and the performance is better: the Schmidts are really nicely engineered and will go on for ever, but they are a lot of money unless you can get one secondhand - they do turn up on ebay and can be reasonable.

In terms of lights, B&M are probably the manufacturer to look at. I've just bought a Cyo Senso Plus - again, pretty expensive here but I found a seller on German ebay who was doing them for EUR 50 or 55. OK, that's still not cheap, but they're a good light - same optics and light emitter as the Schmidt Edelux, which is seriously pricy. LED lights are definitely the way to go these days - more efficient, and no bulbs to blow.

If you want to see and/or try a Schmidt with the Cyo, let me know - happy enough to show it off ...

http://solidlights.stumpie.com/buy/

Good topic, I was just looking for a dynamo hubs and light set.

I've heard of the reputation of the Schmidt, but couldn't afford to spend that much on a dynamo hubs that'll just be use on an everyday bike, the Shimano Alfine seemed like a great option.

Also, does anyone know what this light is? as far as I can tell it's a Shimano, but no more detail than that, it also would be nice for it to have battery in order to keep the light on even when the hubs isn't spinning;

This is worth reading.....regarding SON Hub Dynamos.

The Schmidt Dynamo front hub or SON (Schmidt's Original Nabendynamo) weighs 1.5 lbs and has significantly less drag than either tire driven dynamos or any other hub dynamo. Made by Wilfried Schmidt Maschinenbau in Tübingen, Germany, the hub is quiet and reliable, and is designed to give at least 50,000 kilometers of trouble free riding between servicings.

Sorry if I sound like an advert.

Sturmey Archer have reintroduced a dynamo hub - Incidentally 'Dynohub' is a Sturmey Archer trademark
http://www.sjscycles.co.uk/product.asp?pf_id=12778&src=froogle
This is the X-FDD with front brake as well.

I have no idea if it's using the old dynohub tech or something more modern, but I'd be interested to see a comparison featuring both this and the old GH6 compared to the Shimano and Schmidt versions.

The old GH6 (or AG/FG geared dynohubs) have completely undetectable drag. All this talk of it being like going up a hill seems alien to me. How can Shimano copy something and then make it worse?
The Sturmeys also came with the options of two sorts of battery back-up. One (the dry battery unit, or DBU) was manually operated by the switch on the lamp, and the other (the Filter Switch Unit or FSU) automatically switched to battery back-up when the power dropped below a certain threshold. Again you could use the switch on the lamp to enable or disable this unit.

Do the modern equivalents offer anything like the FSU?

Yep, a capacitor, give you a min or two of backup light when sat at a junction..

The old GH6 (or AG/FG geared dynohubs) have completely undetectable drag. All this talk of it being like going up a hill seems alien to me. How can Shimano copy something and then make it worse?
?

The hill equivalence is just to show how little drag there is. It is never going to be a purfect system, even the son has drag.

The Sturmeys also came with the options of two sorts of battery back-up. One (the dry battery unit, or DBU) was manually operated by the switch on the lamp, and the other (the Filter Switch Unit or FSU) automatically switched to battery back-up when the power dropped below a certain threshold. Again you could use the switch on the lamp to enable or disable this unit.

Yep, a capacitor, give you a min or two of backup light when sat at a junction..

that, yes perfect, it's always annoying when the light start to dim at a crossroad.

I'm planning to get the dynamo hubs and the Mavic A119 rims, the beauty of this is that when I want to do the Dunwich Dynamo (the name's purely coincidence I tell you), I can simply put that wheel on my main bike and cycle away into the evening.

I use a Schmidt hub with a Solidlight that utilises the fact that Schmidt hubs put out 12v over 12mph so the second led comes in.

Because the Solidlights are LED they don't give the pool of light on the road but in dark country lanes they are brilliant giving a good overall flood of light.

Around town a Busch Muller 3watt Halogen might give you a better spot of light for seeing potholes etc

There are some new LED dynamo lights that are supposed to be brighter than the Solidlights but I have not seen them yet

There is a good thread on light testing here on YACF
http://yacf.co.uk/forum/index.php?topic=11751.0

and here on AUK site
http://www.aukweb.net/lights/index.htm

I'd be using a Halogen. The one drawback to halogen/reason for using LEDs is battery life. This is not a considation with a dynamo, so you might as well use the decent solution. Even crap dynamos put out enough for a decent amount of light from a halogen.

LEDs don't work as well with AC (which bicycle dynamos put out) at low speeds they flash, and then the light gets more solid, but still flickery at high speeds so you need a bridge rectifier, which reduces voltage.

I bought some of those cheapy-looking bolt-on ones that have appeared in loads of bike shops recently. Freelight, I think they're called. (They have a display unit on the counter with a little wheel you can spin, to pull the magnets past the lights and make them flash). I figured if they were rubbish, one of my kids could have a set on their bikes, cos they'd think it dead cool. Piece of piss to fit - they have magnets bolted across your spokes and a light held on by your wheel nut (prob better suited to wheels with nuts, rather than quick release). When the wheel spins, the magnet passes just behind the light (unscientific adjustment by bending the bracket a little until the spacing betwixt light and magnet is right).

I was quite surprised at how good they are, having heard that they're "nice product, but they're pretty crap as lights". Well yes, they are crap lights if you want to see by them - they're designed as marker lights, so they spray light everywhere, not focus it onto the floor. No shit you can see by them. My mate took my bike for a spin the other night and I was pleasantly surprised at how visible they are - from really wide angles too, which most front lights don't offer.

I bought the slightly more expensive ones with the battery backup. They flash for two mins before turning off, but the battery backup holds way more than two mins charge - they just stop after 2 mins. So the second you spin the wheel once more, they start again for another 2 mins. Never bothered testing it after that, I reckoned that 4 mins backup time was plenty. They might possibly be a bit heavy for some of the weight-nazis on the forum, I don't know how heavy other lights are but given that me + bike + bags + locks weighs in at around 275 pounds, a couple of ounces really isn't breaking the bank on that score.

For a set of lights (you get front and back for your money) that are always on the bike in case I'm ever caught without my main lights, they seem like a good buy to me. No doubt you can get better products but you'll pay more for them and you'll possibly worry about having them nicked.

Cheers Tea_Bee - really good to hear a review of those Reelights - do you recon you could re-wire /re-build the front light into a traditional-style front lamp?... just to make it suit an old school build?

I'm going to be using them mainly in the City, so TBH I don't need flood lighting etc. - just need to be seen.

That said if I did go to the effort of building up a dyno hub I guess maybe I'd want one that gives me options at a later date...

...that's kind of why I wanted to know if there was a happy medium between cost and quality.

Funny, i just bought an old bike with cute mudguard-mounted dynamo lights but was thinking of finding someone to convert them to battery LEDs to retain the look but lose the crappy pre-war technology.

I looked into it a while back. There are some youtube sites + oth websites that have ppl converting old school lamps with LEDs inside.

Depends on your knowlege/confidence of electrics... I'm sure that I'd understand it 10x better if I was still in school.

There is also somewhere that sells a really good replica... think its US and not that cheap (£30+)

I love my schmidt son/edelux combo. The drag is just noticable on the stand spinning the wheel when you switch the light on and off. When riding i don't notice it at all on my tank of a surly. Maybe if you were doing night TTs it'd matter tho ;)
Light output is unreal, i have the version that clips the top of the beam to stop it dazzling cars. Even pointed straight down in front of the wheel it chucks out a ton of light.

Pricey, but worth it for a tourer or night bike(hi spec pub bikes for forum drinks this winter, most lighting and booze friendly bike wins?)

I'd be using a Halogen. The one drawback to halogen/reason for using LEDs is battery life. This is not a considation with a dynamo, so you might as well use the decent solution. Even crap dynamos put out enough for a decent amount of light from a halogen.

The other disadvantage of halogens is bulb life, especially when being used with a decent dynamo. Using decent bulbs and a reasonable B&M light I've blown bulbs in just a few hours (admittedly that was unlucky) but never got more than a few months - I used to carry two spares as a precaution. LEDs have come on loads - I'd say my Cyo (LED) puts out way more light than my old halogen light.

LEDs don't work as well with AC (which bicycle dynamos put out) at low speeds they flash, and then the light gets more solid, but still flickery at high speeds so you need a bridge rectifier, which reduces voltage.

The halogens flash as well at low speeds. And by low, I mean below walking pace, because that's when the LED stops flashing.

I use a Schmidt hub with a Solidlight that utilises the fact that Schmidt hubs put out 12v over 12mph so the second led comes in.

Because the Solidlights are LED they don't give the pool of light on the road but in dark country lanes they are brilliant giving a good overall flood of light.

Around town a Busch Muller 3watt Halogen might give you a better spot of light for seeing potholes etc

How old is your Solidlights setup? If it's more than a couple of years old I'd compare it to one of the newer LEDs (Cyo, Edelux etc) and see what you think - they're very good in light output. Like I say, I'd rate the Cyo way more than my earlier halogens. I think Solidlights may be able to upgrade the LED emitters in older lights.

The hill equivalence is just to show how little drag there is. It is never going to be a purfect system, even the son has drag.

Aye. But you're never going to notice it - like I said earlier, the comparison I've seen is equivalent to a seven foot climb over a mile - simply not worth bothering about.

I love my schmidt son/edelux combo. The drag is just noticable on the stand spinning the wheel when you switch the light on and off.

Sounds about right ... You can feel the individual magnets if you turn the wheel by hand, but as soon as it's got any speed it's not noticeable.

Pricey, but worth it for a tourer or night bike(hi spec pub bikes for forum drinks this winter, most lighting and booze friendly bike wins?)

Aye, sounds about right: be interesting to see the SON/Edelux combination next to the SON/Cyo I've got, as I'm pretty sure the innards of the light are the same. SON, mudguards and rack are a damn good way to add weight back onto a bike though ...

the drag produced is explained by lenz's law, the induced current (from spinning of magnets) produces a magnetic (and electric) field that acts in the opposite way to the change of flux/motion causing it.

I love my schmidt son/edelux combo. The drag is just noticable on the stand spinning the wheel when you switch the light on and off. When riding i don't notice it at all on my tank of a surly. Maybe if you were doing night TTs it'd matter tho ;)
Light output is unreal, i have the version that clips the top of the beam to stop it dazzling cars. Even pointed straight down in front of the wheel it chucks out a ton of light.

From what lights did you upgrade from and how have you mounted the edelux?

Blowing bulbs is pretty difficult on my Raleigh - you can't go fast enough to do it - well you could, but the brakes are so crap you don't tend to.

As always Sheldon has the answer:
I used to have a Dynohub on a tandem, and the bulb consumption was unacceptable. I solved the problem (and some others) by running the Dyno's output through a full-wave bridge rectifier and then hooking the DC in parallel with a 6 volt (5 x 1.2v cell) nickel cadmium battery. This not only provided light when I was stopped, the Dyno would re-charge the nicads, and, when we went so fast that the voltage rose above 6 volts, the low internal resistance of the nicads sucked up the excess, gaining a bit of extra charge and saving the bulb.

This is almost exactly the circuit that was in the Sturmey FSU by the way.

Once the voltage is sorted Halogen bulbs should not be prone to blowing. They keep going for decades in cars. One advantage is that you can easily convert existing setups with barely any electrical skill. 4 Nicad AA batteries and a rectifier would fit inside the front lamp of my Sturmey system. I may try it and report back

From what lights did you upgrade from and how have you mounted the edelux?

Upgraded from a variety of crap cateye/knog/etc lights. Have experience of others bikes with good quality recharageble lights(solidlights etc) and i still think what i have is superior on unlit roads. That said i know way less about night riding than many on here so their advice is probably more sage.

Mine is mounted to the brake hole on the fork(v brake setup on tourer). Pokes just above the cable boot on the brake. Wire from hub wrapped a few times round the fork blade to keep it in place, cable to rear light taped under toptube and excess cable(used schmidts pre made assembly) wrapped around canti cable stop to keep tidy.
Depending on what front rack i eventually get i will move it to either the bars or light boss on rack.

Ta for your comments. I'm going for it as l just sold my dual E6s. These were fine except for slow speed, manually turn the secondary on-off, plus l free up a plug for a charger. Like yourself, l have tried the cateye, knog, dinottes and the E6s were a revelation.

Yes, from what l heard/read the optimum mount position is around the fork crown, although l need to devise a mount for my front rack.