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I have a Batavus Dutch bike for local commuting with a Shimano DH-2R30E 6 volt, 2.4 watt hub dynamo driving a halogen bulb headlight. The light provided is not very bright and I would like to know if I can replace it with an LED headlight for a reasonable cost. If so, what would you recommend?

I should also mention that I would like to bolt the light to the bike in place of the existing light, rather that fix it the the handlebar and unclip it when I leave the bike. One of the major benefits of the Dutch bike concept is that everything is fitted including locks and lights, so it is quick to use for short local journeys.

Given that I will leave the light on the bike unattended, the light shouldn't look too special, and a reasonable cost would be less that $100/£80.

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3 Answers

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Peter White has done a lot of testing of dynamo headlights and has even put together comparisons of luminance. I have the Schmidt Edelux and love it.

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Likewise, I have the IQ Cyo Senso Plus, and love it. It has a brighter beam toward the bottom so you can see the road, and a fainter beam above the horizon to avoid blinding cars. – Stephen Touset Aug 13 '12 at 16:08
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Reasonable cost could mean a problem depending on your budget, because a good LED light for dynamo-hubs should not be cheap.

My suggestions, based on what I've seen (at night, during some randonneur events) are:

  1. From Busch & Müller, the IXON models. Their light is obscenely strong, reaching 100m+ with a good cutoff, thus without annoying other riders or road users.
  2. Schmidt Edelux, which work on the same principle of semi-parabola reflector. I think this is not so strong as the former, but maybe if you like to enjoy THE NIGHT (instead of throwing bird's eggs out of their nests on the trees with your headlight beam), this is a very good choice.

I cannot tell about other models, but it seems to me that they've seen a lot of improvement in the last few years, the greatest one being the abandonment of halogen bulbs (argh!).

Hope this helps!

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Might be easier to just ignore the dynamo and pick up a bike light off a Chinese website. For $30 I got a light with 2 batteries (which means one spare), a charger, a flashlight and a bike mount for the flashlight. The thing is insanely bright and one battery will run for about an hour and a half. I've had 2 or 3 people comment that they thought it was a motorcycle coming up the road. – Kibbee Aug 12 '12 at 16:12
@Kibbee after I felt the taste of permanently available light, no batteries, I wouldn't even think about going back to anything less than 12 hours straight. I imagine that the brightness-per-buck ratio of your light is great, but one hour and a half sounds like a joke! – heltonbiker Aug 12 '12 at 21:35
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(not to mention that the beam pattern for a vehicle light is way different than the radially symmetric pattern of handheld flashlights). – heltonbiker Aug 12 '12 at 21:35
Supernove E3 for more that 200 Euros is not a reasonable cost to me. 50-80 Euros/Dollars could be acceptable for good performance. – Nigel Davies Aug 12 '12 at 21:41
The other thing I implied in my question, but did not make explicit is that I would like to bolt the light to the bike in place of the existing light, rather that fix it the the handlebar and unclip it when I leave the bike. One of the major benefits of the Dutch bike concept is that everything is fitted including locks and lights, so it is quick to use for short local journeys. – Nigel Davies Aug 12 '12 at 21:43
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Any replacement would need to be matched to the dynamo in voltage and load. I'd suggest that you contact the dynamo manufacturer to find out what might work.

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The dynamo has 6V, 2.4W printed on it, so I know that. What I don't know is the voltage or power required for the various LED lights. The manufacture web sites don't make that data easy to find. – Nigel Davies Aug 12 '12 at 22:17
@ngdavies -- First off, the dynamo almost certainly produces AC, and the output is 6V RMS (which means a peak voltage of about 8.5 volts). And the voltage likely varies widely. Any LED lamp would expect DC, and relatively steady voltage. Unless you're an electronics hacker or can find a regulator designed to mate the two, there's no way a standard LED lamp will mate with the dynamo. – Daniel R Hicks Aug 12 '12 at 23:49
thanks for pointing that out. I will do more research on the various dynamos now. Clearly some are compatible with LED lights, or maybe some lights have build in regulators. Hopefully some googling will give me an answer. I will update my question when I know more. – Nigel Davies Aug 13 '12 at 7:55
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For the record: 1) The standard for dynamo hubs is AC, 6V, 3W, so they can feed a 2.4W headlamp and a 0.6W tail-light. 2) Every light built for dynamo use have a circuit inside which converts the AC to DC, regulating its voltage to 6V to prevent blowing the light at high speeds. 3) You can convert, as I did, any 6V (4 batteries) bike light to use with dynamo, but you should be able to build a rectifier/filter/regulator with electronic circuit board. 4) If you can build the circuit, you could very well build (as I did once) the headlight itself with a handful of relatively cheap white leds. – heltonbiker Aug 13 '12 at 12:20

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