Bike Gear : Self-made or Improved

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

Bike Lamp NEW !

Bike Lamp

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:

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

see
below

Step2: The Inner Electrics

You only need very limited soldering know-how, there is only 2 spots you must solder, the rest is screwed.

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.

The Fisnished Lamp

Here are 2 pics of the finished lamp:

Step 4: Mounting The Lamp

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.

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.

Parts:

Lamp
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.

Casing
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.

Lamp-Socket
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.

Glue
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.

Connectors / Plugs
You can use any connector you find suitable. I found the ones shown in the picture optimal. (German: Niedervolt-Steckvebinder @ www.Conrad.de)
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.

Battery:.
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

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

Disclaimer

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

Nicer Hull:
As you can see this is a real budget system. I thought this will have the most interest by other people planning to make a lamp themselves.
My next version will probably be one with a nice outer hull and a quick-release that also contains the electrical contacts of the lamp.
HID:
Another idea is to make a HID (Metal Halide) lamp as the big vendors sell them: lupine nova more
The main problem here is, that the parts are still expensive and difficult to get. More info can be found at the site of Olaf Schultz

Links

Commercial Systems

Other Selfmade Bike-Lamps

Schymik's Page -> Transalp -> Werkstatt.htm
MTB-Biking's Collection
The fat Hippie
www.bikeleuchte.de
tandem-fahren.de (German)with lots of technical background info on batteries and an LED Lamp

More Reviews and Tech Background

http://user.fundy.net/cyclist/reviews/
German review of standard bike-ligths: http://www.fa-technik.adfc.de/Komponenten/Scheinwerfer/
I mainly have this link here, because I am fascinated by the HID (Metal Halide) lamp in the test.
Here are pictures of the beam: Awesome ! http://www.fa-technik.adfc.de/Komponenten/Scheinwerfer/vergleich.htm


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	see below

Step2: The Inner Electrics You only need very limited soldering know-how, there is only 2 spots you must solder, the rest is screwed.

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.

The Fisnished Lamp Here are 2 pics of the finished lamp:

Step 4: Mounting The Lamp 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.

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.