Bike Gear : Self-made or Improved

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Here are some of my ideas for improving or improvising bike equipment:

Bike Lamp

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The Project  

After being tired of improvising with noisy generators and other unreliable parts, and being frustrated with not seeing anything on forest roads with the standard German 2.4W front lights, I wanted to have a better lamp. There are some commercial systems available which are quite pricey - too much for my taste. On the other hand there are many private projects which were inspiring: Simple, cheap and effective. This is what I wanted to do, so here is my own flavor of a self-made bike-lamp:


lamp-finished.jpg (28812 bytes)

 Pictures, Step by Step:  (Click on thumbnail for bigger image)

Step1: Get the parts
You will need the following parts: 

  • Lamp                    -  ideally 35mm sealed Halogen

  • Lamp Socket        - or my cheap replacement

  • Outer Casing        - ideally a metal one

  • Electrical Plugs      - 3 of them: lamp, cable & charger  

  • Battery                 - rechargeable lead ~3Ah

  • Silicone Glue         - heat resistant

  • Cable                     - some for the battery and 2 short pieces for inside the lamp


Step2: The Inner Electrics

You only need very limited soldering know-how, there is only 2 spots you must solder, the rest is screwed.
lamp-build-800.jpg (39579 bytes)

Step 3: The Rubber Cover

To make the lamp more resistant and to have a better grip when mounting it, I have simply slipped a section of an old bike-tube on the lamp. With the right diameter, there is no need for gluing, although you can do that if you want to.

lamp-with-tube.jpg (22784 bytes)

The Fisnished Lamplamp-finished.jpg (28812 bytes)

Here are 2 pics of the finished lamp:

lamp-finished-back.jpg (21842 bytes)

Step 4: Mounting The Lamphandlebar.jpg (38493 bytes) 

Now you can attach the lamp to the handlebar. I chose a simple version, which is still very effective: I use a larger rubber tube (e.g. from motorcycle) and cut off one ring. This ring is simply wrapped around the lamp and the bar as seen on the picture on the right.
Other options are to use 2 Hose clamps or to buy a cheap commercial lamp with a 'click'-attachment, cut that off and reuse it. 

lamp-attach.jpg (60373 bytes)

Step 5: Mounting The Battery

For the Panasonic 3.4Ah this was pretty simple: It snugly fits my bottle holder without modifications. To make it look a little nicer, I have put a cloth cover on it. Because I mainly use the lamp in winter, when I don't drink much on the bike, this is an ideal combination.

battery-case.jpg (52910 bytes)




There are Halogen Lamps that are ideal for a bike lamp, which already have a sealed glass front:
You can get them in 35 & 50mm diameter and a large variety of  technical specifications (Volts, Watts and BeamAngle - most of them are 12 Volt) I have used   20W / 10º  and  35W / 30º lamps.
The 10º is a little narrow for off-road use, but good on the street, when you don't want to blind cars.
Note: I have read many times, that the quality of lamps is important: The better ones seem to produce much more light at the same nominal Watts.

lamp-alone.jpg (11861 bytes)


I searched a while for a high-quality aluminium tube to build my lamp from, before my father brought a piece that was the ideal fit: A can of hair-spray. In the meantime, I have found another nicely-fitting can, that is available in many colors and odors ;-)  Don't be afraid by the thin walls: You can easily put a dent in these cans, but that is actually not a problem: if you want to mount the lamp directly on the handlebar with a rubber-band, like I do it, this will improve the friction.

casing.jpg (17322 bytes)


You can buy the regular ceramic halogen-lamp sockets, but they cost nearly as much as the lamp.
Much cheaper is my solution: just cut apart the screw-connectors ( E:"terminal block", D:"Lüsterklemme") and screw them directly on the lamps rigid feet.

screw-connectors.jpg (14135 bytes)


Because the lamp is directly glued into the housing, you will need heat-resistant glue. 
Silicone glue is ideal for this, you can get it in different sizes, but will only need very little of it. 

silicon-glue.jpg (19377 bytes)

Connectors / Plugs

You can use any connector you find suitable. I found the ones shown in the picture optimal. (German: Niedervolt-Steckvebinder @
I don't use any switches, because it is convenient enough to plug-it-in = "On" / pull-it-out-a-bit = "Off" . This saves me from another electrical part that might corrode and fail.

lamp-plug.jpg (11724 bytes)


First you have to decide for a general battery type:

  • NiMh  :  + High Capacity,     + Low Weight,  - High Price, - High inner Resistance (*)
  • NiCd  :   - Low Capacity,     + Weight,          0 Med. Price + Lower inner Resistance
  • LiIon:     - Way to expensive + Lowest Weight
  • Lead:     + Low Price,  + Low inner Resistance (*), - High Weight
    (*) High inner resistance means that you will loose a lot of power in the battery for bigger lamps (high current)  

I decided for the lead type, as do most of the self-made projects I have seen. The price-value is certainly the best, and there are lots of sizes available. Panasonics seemed to have a fair price, and they had two sizes I considered: 2.2Ah and 3.4Ah. In the end I went for the 3.4 and it was a good decision. With my 20Watt lamp I should get ~2 hours, but in cold temperatures it is often just 1'15h

Technical Data Picture
LC-R122R2P   (LCR12V2.2P) 12V 2.2 Ah 177 x 34 x 60mm 800g

battery-panasonic-22.jpg (11650 bytes)

LC-R123R4P   (LCR12V3.4P) 12V 3.4 Ah 134 x 69 x 60mm  1200g

battery-panasonic-34.jpg (15042 bytes)

battery-panasonic-34.jpg (12176 bytes)


Please note that the use of this lamp on public roads is not legal in Germany !
Although you will usually not get into trouble when using reasonable versions (10-20W / 10º) and take care that cars are not within your beam (I never had someone flashing his lights at me, indicating that he would be disturbed) it is still not legal to use it. If you want to be on the safe side, it is only to be used off-road !

Next Steps


Commercial Systems

Other Selfmade Bike-Lamps

More Reviews and Tech Background