I've been doing a lot more cycling in the last year since moving to a new town and have really enjoyed it.

I had a fairly crappy bike though and went to a secondhand store quite far away to get a good bike at a nice price.

One big issues is there is what I assume is the bike light in front of it (just one) but I see no way to get it to actually turn on, which means I can barely cycle now.

I used to have the lights where you move that part down to touch the wheel and the movement causes the light to go on (best way I can explain it). This doesn't do that. I also don't see any on/off button or basically any obvious way to get it to work. The store I bought is really far away as are the good bike stores (I live in a small town.)

I've started to wonder if it's really a light or a reflector - although it looks like the former. Any help please?

the 'light'

  • You used to have dynamo lights, plus a rim dynamo. It could be that this is a dynamo light also, you just didn’t get the cables for it.
    – Weiwen Ng
    Commented Dec 13, 2019 at 22:49
  • Can you take a picture of each wheel hub? You might have a dynamo hub that just needs wiring to the light
    – Andrew
    Commented Dec 13, 2019 at 22:55
  • Or maybe even the bulb is simply burned out!
    – Affe
    Commented Dec 13, 2019 at 23:25
  • some dynamo lights have a switch on the back of the reflector housing, yours probably doesn't though from the looks of it (usually only newer dynamo lights have such a switch). It does very much look like a dynamo light (the one in your picture) Commented Dec 13, 2019 at 23:27
  • As with anything electric: Follow the cables, and you'll find the power source. Somewhere along the way must be the switches, if any. Once you know where/what the cables/power-source/switches are, you'll know how to turn it on. And if that fails, you may need to replace the light bulb. Commented Dec 13, 2019 at 23:47

2 Answers 2


This is a halogen light. Such lights are usually powered by a bottle dynamo. That is a small electric generator that is driven by the front or the rear wheel. There is usually no switch. One simply engages the dynamo by pushing it down, such that a spring presses it against the flank of the tyre.

Some bikes have a hub dynamo instead. In this case there might be a small switch at each light. A hub dynamo looks like a very large front hub (central part of the wheel).

If you have such a dynamo make sure that the light is connected to it. Follow the wires from the lamp to the dynamo. On older bicycles with bottle dynamos there is typically only one wire. The bicycle frame serves as common ground connection.

Check if the dynamo is properly pushed to the tyre and that its wheel spins when you spin the tyre.

The bulb in the lamp might be defective or missing. Replacement bulbs are not very expensive. But they may be hard to find today. An inexpensive led lamp might be a better replacement, as such lamps are considerably brighter.

Finding the fault may be a little tricky without a volt meter or other means to test electrical connections. If you cannot got to a bike shop anyone who is handy with simple electrics may help you out. For example, electricians or car mechanics.

  • 3
    +1 but note that halogen gen light bulbs only last around 100 hours (that's what I get on my E6s) and needing to replace them is common. In parts of the world where generator lights are common, getting the bulbs is no big deal, bike shops or the internet will have them. The bulb on this light is likely accessed by grabbing the entire "light" part and turning counterclockwise. Commented Dec 14, 2019 at 1:43
  • and, if one of the halogen bulb burns through, the other will follow: a rear one immediately after the front is done, the other way round the front one will last a bit longer. This is because the dynamo produces a current rather than a voltage, which means if one of the loads is gone, the other will get the full current (the voltage will increase accordingly). Commented Dec 16, 2019 at 20:27

A brief Google search of "Soulbitez halogen lights" returns hits where almost all the lights are Dynamo powered. My idea is that, like the light you mentioned as having previously, this one in the photo may have to be connected by a missing wire connected to a Dynamo. I do believe it is a light, as why the word, "halogen" included on the piece? It is useful as a reflector, but rather large to use only that function.

Look for a way to access the bulb and a place where a wire may have led from the light to the Dynamo. Accessing the interior will surely result in observations that will reveal whether the light has an area for batteries and would be then not likely to be Dynamo powered. I'd begin this exploration by focusing on the thinner area on top where it appears there's an opening where a screw or the like might be. Just forward of that, there's a section of the seam that is a little wider where a thin coin or flat screwdriver fits to pry the sections apart. Do look for a screw or other fastener within that hole to the rear of that seam which might prevent the sections from being pried apart.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.