BIKE LIGHT 500 Lumen "Mt.Bike" for Under 10 Bucks NOW W/ LED TECHNOLOGY by Veggiecycle





Introduction: BIKE LIGHT 500 Lumen "Mt.Bike" for Under 10 Bucks NOW W/ LED TECHNOLOGY by Veggiecycle

Most good rechargeable tungsten halogen Bike Lights that put off a good deal of light (200 to 600 lumen) cost a ton of money 75 to 200 bucks. I took my really expensive light apart and found that its just a bulb you can buy anywhere for $ 4.00 and some rechargeable batteries. So here is a CHEAP way to build your own with part that you can get from Home Depot (mostly) This is a no frills light. I didn't put a switch on this one. I have been adding switches to my new ones.
........................NEWS FLASH.. I have added an LED for better energy management  See the last step for LED upgrade......................................

I have another bike light

Step 1: First You Need a Body. I Found That a Trap Adapter and a PVC Female Cap From HD Plumbing Dept Works Good.

Trap adapter ABS-DWV 1 1/2 x 1 1/4 $1.14
Female Cap VPVC Sch 40 1 1/4 (threaded)$.78

Step 2: I Use a MR16 Bulb Its the Kind Made for Track Lighting

Next I use a MR16 (WITH THE LENS BUILT IN) bulb its the kind made for track lighting. I use 12 volt only and I like a 10, 15, or 20 watt bulb. You can get the 20 watt from HD for 4.95 the lower watts bulbs you need to get online from a lightbulb dot com place or a specialty light bulb store in your area. You will also need a MR16 socket that you get from a specialty place for $2.00 and a Conduit Hanger and 1/4 inch thumb screw to replace the screw that comes on the hanger (to make it easy to adjust or leave the screw on and crank it down and forget about it ) and a nut and bolt to hold it to the Body

Conduit Hanger w/speed thread size #0 3/8-1/2 5pk $1.90 HD
MR16 Bulb 20 watt Aprox $5.00 HD
Thumb Screww 1/4 " 3pk $1.29 HD
Lock nut (nylon insert) #10-24 4pk $1.29 HD
Bolt 1 inch long #10-24 4pk $1.29 HD
MR16 Socket $2.00

Step 3: No Hub Coupling From the Plumbing Dept

Next a No Hub Coupling from the plumbing dept to make a tight sleve to hold the light bulb in place and make it water (tight??). You are gonna pull the rubber part out and cut it in half but leaving the middle rim on one side then trim it to abot 3/4" to an inch total width. (I hope that makes sence once you start cutting it)

No Hub Coupling 1 1/2" to 1 1/2"

Step 4: Kinda Together Showing the Rubber Seal Holding the Bulb

We kinda jumped ahead with this pic so you could see what this was for.

Step 5: Drill a Little Hole and Tighten the Hanger on the Hub

Just use any small nut and bolt to hold it on. I have been using wing nuts, and lock washers so I don't need any tools for this step. FLASH new pic update The wing nut and bolt and lock washers is the setup I like to use now.

Step 6: RCA Male/female

I like to use an RCA cable. Cut it about 3" from one end. Drill another small hole in the cap or body and stick the short piece through and soider it to the socket.

RCA male/female end cable $3 Radio Shack

Step 7: Battery This Is Gonna Cost You a Little Bit

You need to find at Radio Shack or a specalty electronics supply for a 10 AA batteries holder. Solder the other end of the RCA cable to it and ....
The best battery to use is a Nickel-Metal Hydride or NiMH 2500 mAh I found the Energizer from HD the best price. You need 10 cuz they are 1.2 volts each 10x1.2 = 12 volts. Put the battery pack in your underseat bag or in a water bottle. The light should work for 3 hours with a 10 watt bulb and 10 2500 mAh batteries. Or 1 1/2 hours with a 20 watt.
If you have any questions drop me a line....

10 AAbattery holder $1.00
Energizer 4-Pack AA NiMH Rechargeable $8.97HD
Energizer 4-Pack AA NiMH Rechargeable w/charger 17.95

Step 8: Put It All Together And...

It should work like a charm..
I got this bike water bottle battery pack that is 5 mah with the quick charger from They have tons of great batteries on that site.

Step 9: LED Is All the News. So... I Have Added a Simple LED Upgrade

Everyone is running LED on their bikes now, and why shouldn't they?? LED lights are cheap, have tons of light and use a lot less power. When I posted this project in 2006 LED's were just hitting the market and cost a ton of money. The market has changed and now you can buy good LED lights for a great price.
But.... There is still the DIY factor (that's why we are all on here, right?)
Here is a simple way to build a LED bike light without having to mess with any circuitry, little parts or soldering.
I just went to my local hardware store, light bulb store or online and bought a  4 Watt LED MR-16 It is rated at 300 lumens or a 5 Watt at 500 lumens and plug it in.... POOF!!!  like magic your done!!!



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    not bad idea just use 3 or 4 cell of 18650. as power supply.

    with your led.

    great, I've made something very similar maybe 12 years ago, I used to cycling in the woods by night, and I had a 20watt light on the bike and a 10° 20w on the helmet, it was awesome!

    This works great and has extended my biking hours, thanks a lot. One thing that I hadn't heard anything on and would add is that bulbs range a great amount in beam angle. The one I picked up for cheap on amazon is almost a 60 degree beam (categorized as a wide flood light), spreading 400 lumens out over a large area. I would suggest a narrower beam, since it seems that a decent amount of my light is scattered in random directions and it does me no good. I'll be ordering a 30 degree bulb relatively soon and will report back (hopefully with pictures) with the results of bulb switching.

    There's lots of comments already, but I just wanted to add my thanks to the long list. I put this light together today, and I am quite pleased with the results.

    I assume your batterys last a lot longer eh?

    Depends on the batteries. To convert a battery's amp-hour capacity to watt-hours multiply the amp-hours by the voltage (12) and then consider what wattage of bulb you're using. For a 20 watt bulb with 2600mAh batteries you're looking at 1.56 hours theoretical run time, and twice that for a 10 watt bulb. Concerning the project: rather than drill a hole for the conduit hanger I just reused one of the hose clamps from earlier to attach the device around the narrow section of the light. it worked out very well. A bit of rubber or cloth is good to increase friction with handlebars and prevent it from sliding. You could also paint a little rubber cement in there or something. Any ideas on a trickle charger circuit for this? Just needs to output >12v and ~90 milliamps and it would be perfect to leave it plugged in at night. Kind of defeats the points to spend $30 on a charger, $20 on batteries. :p

    Mmmm... Don't be fooled by those manufacturers numbers. Those capacities are obtained at a much lesser discharge rate, more like 1/2C. At 20 watt your at (2,6/ (20/12)) 1.56 C. So you can't expect less run time. Duracell provide very good information on their website... You can aslo use a cheap Sealed Lead-Acid 12v battery wich cost 10$ and a generic charger for about 5$ - 6$...

    My experience with 12v 7ah SLA batteries is that they are HEAVY (6-7 lb), and they do not like being discharged at the rate that these MR16 bulbs take! I get run times of 45min to 1 hr. Sometimes more if I stop running the light for 10 min or so between runs of 30min. Also, they fail in cold weather, which is the main time I need my light!

    i made 1 of these lights but i found if you use the led replacements instead of halogen bulbs your batteries last a lot longer. run time on my light with a 50w halogen was about half an hour and with the 60 led bulb its about 4 hours

    Thanks for the instructable. I will keep playing around with the MR16 because I like the light frequency it puts off, and its a fun hobby. Try batteryjunction com too for your lighting hobby or just buying a complete light. They cater to cyclists, cave spelunkers, and hunters.

    I really like your idea of the RCA connector. That looks like a strong, low resistance connection, and should not pull apart too easily.

    Why not just use one of those rechargable battery packs they sell for use for an RC car? A lot more compact and cheaper, and still 12v.

    1 reply

    You could do that too, but if any of the cells weaken or are damaged, you have to replace the whole unit. This system (aa's) would allow individual batteries to be tested and replaced more easily. Also you could use up gift or leftover AA standard batteries. Some people even recharge alkaline AA's with the new home chargers ($40) that are popularized through dpt stores.

    i wonder if you could use this same configuration to replace a bulb on my 50cc scooter...which is 35amps? the stock bulb is vastly weak

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    I ride a motor bicycle, and the 20w 12v narrow flood beams do NOT work well in traffic. this bulb is WONDERFUL for off road riding at 5-15mph though. SInce you will have a bigger battery or generator system, you may be able to get satisfactory results by using 2 of these, one with a narrow flood beam and one with a narrow spot. If you can run a 35watt bulb with your scooter, just buy a fog light or dune buggy light, probably you will be happier.

    That's great! I was wondering if you could get enough run time from AA's to make it worth bothering with. Look on batteryspace com for DIY light supplies and batteries. They cater to bicyclists fed up with overpriced kits. I use a "hip pack" for my current battery (6lb!) so I think 2 10 * AA's should fit in there great.

    Howdy. I used the same bulb and a PVC pipe reducer. The threaded part is used to cap the lens onto the part that held the bulb, and the plug is held on by a ziptie strung through 4 small holes on the base. Yours looks really good though. I like the thumbscrew idea!

    Why wouldn't it be better to use just 1 long battery holder. then using to of them. u could have that go any where on yr Bike. i would do that in stead of to or more. & i don't no y u couldn't use a Solar Powered Unit like they have at Harber Freight. people use them to keep there Battery charge up in there car. so Y can't u use that 4 yr Battery on yr Bike light

    I am very excited about this project, however I keep getting curve balls thrown at me. I bought a battery pack today, however it doesn't have the red and black wires connected to it, just a pos and neg stud. Is there anything I can do, or do I need to find another battery pack matching yours?
    Also, I was advised at RadioShack that Hooking Wire would also be usable in a project like this, however without the red and black wires, I'm wondering if I've just collected a bunch of pieces that don't fit together.

    Thanks so much!