Easy-peasy Bolt-on Halogen Bike Light




I got the idea for this from reading all the numerous instructables using interior fixtures. Aesthetics were a concern on my old Schwinn Collegiate and, taking a chance on these auto fog lights I found, I was pleased to find that....damned if it didn't bolt right on there, and work to boot. -Seriously, the hardware was the same as my brakes. I just switched the nuts. Another improvement, I think, is the battery. While it weighs more than a cordless drill battery, it's much less than one for a motorcycle, and costs less than either (I think?).
Ain't she handsome?


Step 1: Buy the Lights

First step, I guess: I went and bought these from the Wal-Mart. They're 55w "driving lights." For the two, with hardware, some wiring, and a switch, they run $15.

Step 2: Aaand the Battery....

Here's how the Cabela's website has it pictured. With the charger, it runs something like $29.95. The charger's some "universal" deal, so if you've already got a 12v battery charger, knock $10 off the total. Bass Pro has the exact same battery, I'm pretty sure, but tacks on $5 for their sticker.

Step 3: Battery Mounting

I picked up this tool bag at the Harbor Freight -$4 (God blessem). With the help of some velcro (lots and lots of velcro), also purchased there, I fashioned it so's to strap on to my rack. Then I sprayed some silicone waterproofing stuff on it, hopefully, for to protect the battery. The tool bag was just the right width, by the way, with a decent chunk of cardboard in the bottom to help it keep its shape.

Step 4: Inside There

I put the battery towards the front of the bag (and peeled that Cabela's sticker off. Listed is more details about the battery). Again, luck would have it that the thing fits in nigh-on perfectly (just slightly wider, but the bag gives enough where you don't notice). On the bottom and backside of the battery, I attached some big fat "industrial strength" (so it was certainly billed) Velcro. To get all this hook-and-loop to affix to the bag, btw, I used a goodly amount of Gorilla Glue (I'm not much of a seamster).

Step 5: The Total Package

Did I tell ya easy-peasy? All I'm leaving out is the wiring, I guess. I used an old printer power cable with some clips attached and ran it under the bike, attaching with zip ties. The switch, I used another zip tie to attach it to my brake grip.

Step 6: Ta Da

Here she is, all lit up. Don't look too long, it'll leave a purple spot.

Step 7: Another Sample

Did this with the garage door closed, almost total blackness, from about 15 ft back from Mr. Selleck. A better showing would be somewhere out on the trail, I know...Trust me though, works like a champ.
As for battery life, it's yet to be seen. I don't wanna let the thing run completely out for fear of breaking it. I do know that I've made several trips right around the 40 minute mark, and the thing's yet to dim.

For a grand reckoning:
Bag: $4
Waterproofing spray: $5
All the velcro: ~$6
Battery/charger: $30
Lights: $15
= $60

...yow. First time I added that up, actually. A bit more than I figured. Still, $37 for the light and battery and charger ain't bad (yes, I halved the light cost...I'll find a use for that other one yet). I may mount it on my other Schwinn, rotate the battery/bag between them.



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    27 Discussions


    Reply 6 years ago on Introduction

    Thanks, friend. I upped the ante recently and added a solar charger/trunk/stereo/12v accessory power source, made out of an old make up case. Here's some pics: http://imgur.com/a/YHRIs

    I can post a parts list later, if you'd like.


    Reply 6 years ago on Introduction

    Very clean. I just added your instructable to my Cycling with Harbor Freight Guide" You may want to add an update to boost views....?


    Reply 6 years ago on Introduction

    Oh, I thought about it. It took me a ridiculous amount of time (3 years) to finally put it together, though. -Any pride or excitement about it kind of got snuffed out by the time I took those pictures.

    And it's not as clean as it might appear in those pics (and nowhere near as clean as I'd like it to be...I'd like to finish out the interior, for one).

    I do thank you for the addition, however. This new box incorporates Harbor Freight's cheapy 12v solar panel, in fact. I'll have to check out the guide.


    Reply 6 years ago on Introduction

    Please do. I find Harbor Freight motivates me like a scrap yard. Its junk, but its great junk! Then I just narrowed it to my favorites of cycling AND Harbor Freight.


    7 years ago on Introduction

    this is a good guide ...but can you please clarify the run time of the battery set up in hours or minutes , thanks.

    1 reply

    Oh, I think I posted it somewhere, but I've ran it right up to an hour per charge and there's yet to be any dimming.

    Does that help? If you wanted to do the math (and look up the light info), the battery is rated at 8 amp-hours, meaning it can provide 8 amps for 1 hour.

    I'm between homes right now and well away from any of this business, or I'd look up the lights' rating, as well.

    All I can say is that I've never had a problem -always enough juice for what I needed (-Plus some. Again, no dimming...and I've not been all that good about recharging).

    Hope that helps?

    the chrome looks good. im working on buildiing up a beach cruiser i found in the dumpster. im guessing the other alternative would be to install the square harbor freight off road lights and just paint thehousing.

    5 replies

    Yeah, seems like any 12v auto lights would work a-ok. Wal-Mart was still stocking these things as of ~a month ago, though.

    An update: I actually did go down to Battery Outfitters and purchased a smaller version of this battery. I'm working (there should be some big quotes around that) on putting it in an old metal file card box, with a solar panel on top, with speakers, usb power on the inside and a cigarette lighter outlet on the outside.

    I got waaaaay too ambitious on that one. It's probably 85% complete, but it's just so damn tight in there, well...I got discouraged and then distracted.

    You know what, I just saw what some of your "favorites" are on here. Damned if others didn't beat me to it. Ah well.

    The batteries are really something, I can't stress that enough. Good luck on your bike!

    heres my finished product for my cruiser. i bought harbor freight lights modified the reflector and put in high output LEDs. BTW do you have pics of the reflector of the bulb? i plan on modifying the same lights for my friends bicycle with high power LEDS. actually an RGB led to make man colors


    Good lookin, man!

    Here's some (more crappy cell phone) pics of the reflectors. Fortunately, I just stumbled across the spare last night and had it handy. Unfortunately (for both of us), they appear to be a reflector-bulb all-in-one type deal, so I'm not sure how much trouble it'd end up being, trying to modify them. They're roughly 1 and 15/16" across the face (lip to lip) and 7/8" deep. -Maybe you could find a suitable, more modular replacement.

    Please, do share your results. Thanks for the comment.


    interesting. i still havent bought the housing yet so instead it might be better to buy a purpose built bullet type bike light and modify. theres a few builds i found online. thanks for the pix. ill come back and post pix when im done

    oh and i put rear lights. theyre 99 cent store "Plant Lights" i just soldered a wire and hooked up to a 9 V battery and painted the LED blue with some fountain pen ink thought u might like


    Reply 9 years ago on Introduction

    Sorry it took me so long to respond. That battery is really something, it turns out. I've gone on rides up to 45 minutes with the light on, and it's never so much as dimmed. I've not run it fully-out for fear of damaging the thing, but... I participated in a St. Patty's day parade here recently and loaned it for use on a mobile merchandise float. It powered a bunch of blinky lights and one of those J.C. Whitney novelty "aaa-OOO-gah!" horns for the duration (something like 3 hours). I've been real impressed with it. Should it crap out on me, however, I was screwing around a Battery Outfitters the other day, and found it (sans Cabella's sticker) plus a couple of other models -same voltage- but half the size. It is a heavy SOB...puts a man to thinkin.


    10 years ago on Introduction

    Update, here: The Gorilla Glue, as the packaging did warn me, is not meant for use on fabric. The big velcro pieces (that which I used on the battery) had one side sticky, one side with the hook/loop. -That, right there, continues to hold just fine with the aid of the Glue. The straps on the bottom, however, were double sided hook and loop. Those have not held. I had to sew it up last night. -No easy task. Just an FYI, there. Maybe rivets would be the way to go.


    Reply 10 years ago on Introduction

    The roomy once went as Magnum P.I. for Halloween (complete with too-short shorts and a nice tight polo). That disembodied head o'Selleck served as his mask. I'll ask him about posting his how-to.