I'm curious if anyone is using dynamos and LED lights? I've looked into dynamo hubs, but they are quite expensive and generate far more power (typically 6W) than a normal LED light requires. Has anyone found a less expensive dynamo solution that provides enough power for a 3 bulb LED light?
Thanks

There are several high-powered LED headlamps made for 3W, 6V dynamo hub applications: Busch & Mueller IQ Cyo and IQ Fly lamps and the more expensive Schmidt Edelux and the Supernova E3.

As to other dynamo solutions, a wheel driven bottle generator or a bottom bracket generator, inexpensive 6 volt bottle generators can be had for about $50 (12-volt is another story, those are expensive). All-in, you could have a bottle generator and state-of-the-market high-powered LED for between $125 and $160, US. This is for a headlight to see by, not just to be seen with.

How many lumens does a typical dynamo hub / light throw?

edit: at say, 18 mph?

I always say buy quality once and don't regret it. Dyno hubs are the way to go.


Depending on your light, you could be getting 600 lumens at that speed.

This site shows that at 18mph, most dynos are at max wattage.

Just to ask, can someone point me at some sites that sell dyno bubs? I had one on a bike and really liked it. Unfortunately the airport baggage people stole the bike in Beijing (that is another story).

Peter White cycles carries generator hubs and generator lights. Lots of info on the web site too regarding lights and generators they offer. Ordering can only be done by phone or letter as they are not equipped to do internet sales.

https://www.peterwhitecycles.com/index.html

As to output levels, the current brightest commercially available generator light seems to be the Busch & Muller Lumotec IQ Cyo at about 80 lumens. The 600 lumens mentioned earlier is for home assembled multi LED generator headlights. Here is a link to plans.

https://pilom.com/BicycleElectronics/DynamoCircuits.htm

The higher power lights put out considerably less light except at higher speeds with either hub or bottle generators from what I have read.

Thanks for the info. I shall not regret spending on my Dinotte and Niteriders just yet. I bet at night in rural areas your eyes would adjust just fine to the lower output of commercial LED's for a dynamo.

I use a Schmidt SON Dynamo hub, Supernova E3 headlight and wired tailight. I have been very happy with and highly recommend this set up for those looking at this type of system.

Velo Orange sells the Shimano dyno-hub pre-built into a wheel for $160.

https://www.velo-orange.com/shdyhubwh.html

If you look at the cite you linked, there are switching electronics schemes that fix the low light at low speed problem by switching out some of the leds. Peter White says that the Supernova E3-D triple puts out too much light for road use. Not sure if I believe that, but unless it has 3 SSC P7 or Cree MCE, it's only putting out around 300 lumen.

I've got Reelight LED lights. No dynamo needed, just a couple of magnets on each wheel.
https://www.reelight.com/

If you switch out some of the LEDs then I have to assume that the light output is still reduced by the number of the total system LEDs that are turned off versus the number that are on. I read some parts of the web site but missed the part with the LED switching circuits apparently.

I agree though that light outputs are frequently overstated and very few people can afford to invest in an accurate Lumens measurement test setup. The high intensity LEDs you mention require more current I believe than most dynamos can put out based on flashlight use specifications I have seen. With dynamos multiple headlights are typicallly run in series which increases the load resistance, raising the voltage output of the generator. As I recall the same technique is used in the multiple LED homebrew headlights.

I suspect that Peter White's statement about light output may be based more on beam shape than total light output. I know the IQ Cyo has a very sharp beam cutoff at the top while reading his comments on the Supernova HL3-D it apparently does not if I interpreted things correctly. When I was in Europe years ago I noted that their headlight beam shape for street legal car and motorcycle headlights had the same sharp cutoff characteristic, much sharper than on American headlights.

It switches between a low speed mode (double voltage, half current) and full wave mode. You need the voltage boost at lower speeds with multi LEDs but you want the higher current at higher speeds. You don't switch out LEDs. The LEDs get driven at up to 500mA which is a very nice drive current in terms of efficiency.

I've run several battery systems and several dynamo systems so have a feel for how well it works... very well indeed. Yes lumen values are often misquoted(moreso in overvoltage halogens I think) but three leds is lots and lots and lots of light. If you're commuting around lit streets a single led is plenty.

Thanks for correcting me.

I use a bottle generator with one of the cheaper B&M halogen sets. Since it came stock with the bike, I'm not sure which set gets specced... but given the pricepoint, there's no way it's a top of the line one. It is a good light for seeing with on a road, but it would not be bright enough for off road use. Potholes don't get completely illuminated, and if you're going more than about 15mph you are at risk of outrunning the light on bad terrain. (since it's trivial to bust 35mph on a bike going downhill...) There is a standlight feature, and it runs for at least a 2-3 minutes when the generator isn't receiving power.

The generator I have is fairly good, but it will fail in wet conditions. Water will cut friction enough that it can't generate light anymore. Since one of the reason I wanted a generator light system was for riding in the rain, this is irritating. I'll eventually need to upgrade the front wheel to a hub generator to eliminate this problem.

Bottle generators also chew on your tire. Not a *lot*, but I do expect the rear tire to wear out sooner than it might otherwise. And it means I don't run lights all the time, even tho I think it'd be a good idea.

Lastly, a bottle generator makes it a bit harder to pedal. It usually feels about one cog higher than it really is.

My current commuter bike has a Nexus Generator hub and the Lumotek Oval LED light. It provides enough light to be seen, and when riding in urban areas is fine by itself. When riding in more rural, darker areas, I supplement it with a Dinotte battery powered light. I am in the process of building up a new commuter, and I will be using the Schmidt Dynohub and the Innova E3 LED headlight. I am hoping that with the new setup, I won't need to rely on the Dinotte as often.

Just a point to take note of: When you start comparing the upper-end LED dyno lights, it's not the lumens to concern yourself with, but rather the lux rating at a specified distance.

Lights like the Cyo, E3, Edelux and IQ Fly are all pretty similar in the total light output, but the shape of the beam will increase the lux (lumens/m^2) reading. With my Supernova E3 side-by-side to a friend's Edelux, he was throwing a lot more useful light to the road surface because of the Edelux' shaped beam optics. Of course, my E3 symmetrical beam throws enough light to the sides and top that we could read roadsigns in the distance without our helmet lamps, so there's benefits and drawbacks to each.

I just got a Lumotec Cyo, and it provides all the light I need for riding in absolute dark while being 100% comfortable (and I'm very very picky about having enough light), and enough light for riding like 80% comfortable in rain or in sparse city lighting (where you need more light because your night vision is affected by the ambient light). Someone less picky would probably say it was good enough for anything. I really love the shape of the beam - it puts light right where I need it.

If I wanted more light, I'd add a helmet light so I could point it to see around corners.

I'm just putting together a 2 led headlight with a very simple circuit. It looked very impressive riding around the parking lot in daylight, I mistakenly looked at the leds and saw spots for quite a while. The leds are quite bright at low speeds. They are flashing at very low speeds, dunno if I can fix that.

Ive been running a Shimano 71 (ultegra-XT) dynohub for almost a year and it has performed flawlessly. My only concern is in 2 or 3 years when it comes time to service the bearings, this is a tricky procedure requireing some care You dont want to sever the live wire by mistake.
It powers an IQ Fly which puts out plenty of illumination, well shaped for any road riding and good for low speed tracks.


Previously I powered halogen bulb dynamo headlamps using either a 6v battery or a sidewall bottle dynamo. The battery is useful on slower sections and in the mud/rain but needs management.
The bottle dynamo on my touring bike was for occasional use but I ended up riding one winter of daily commutes. The secret of a good sidwall setup is a secure and ridid mount so the spring can press against the tyre rather than rotate the mount.

I've been thinking about wiring a tail light to a front generator hub. How did you run your wire from front to rear?