Introduction: How to Build a $10 Bicycle Whip Light: Be Seen and Be Safe

About: I like to build, create, and invent new things to use in life. Sometimes I like to share them with others, that's why I joined Instructables. :-)
In this Instructable I will show you how to build a Bicycle Whip Light from some pretty common materials.

This idea came to me as I was working on a similar project for an ATV Whip Light (which I hope to post some time soon.

This is a really good tool for being seen when riding your bike at night. It has 3 different setting that can be used, well four if you count being turned off, we can call that stealth mode).

1. Slow blinking
2. Fast blinking
3. Constant on

Any of these are eye catching and can be seen from a great distance.

I have made a video of it in action but the camera didn't capture it well at all. I don't know if it was the camera or the settings, but the light is very bright at night more so than the movie shows. The small you video window virtually blacks out the light in the demonstration. I am pretty disappointed that you can't see it in the video.

Step 1: Safety Stuff/Awareness

Ladies and Gentlemen Boys and Girls in this first step I will try to briefly cover safety concerns of this project.

1. You will be using power tools - Wear goggles or other eye protection

2. You will be using glue - Gloves and eye protection

3. Sharp objects and blades - Use intelligence

4. Heat source - Use your asbestos jacket- Just kidding. Just be aware of things being hot and can burn down your house, or you.

5. You will be using your "I-M-A-G-N-I-N-A-T-I-O-N", ok well maybe not since I have done all of the thinking for you.

Step 2: Materials and Tools

Here are your Material and Tool lists:


1. $10 Coast LED Personal Safety Light (another name for it is a Lenser) at Fyrs Electronics

2. Heat Shrink tubing

3. 1/4 "Fiberglass tent pole, or bicycle flag whip from a bike shop (I used a tent pole this time).

4. 1/4" to 3/8" nylon barb reducing union WATTS for some reason it looks different than mine. I have added a pic of mine.

4. Old a towel rack

5. Nut, bolt, and washer

6. Elmer Ultimate Blue Bull Poly glue or Guerrilla glue


Drill with drill bits

An Acid brush


Heat gun

A wrench for tightening your nut and bolt

Step 3: Modify the Barb and Install

Step you will need to gather your Nylon barb and your tent pole/fiberglass rod.

You will need your drill and a drill bit. Your drill bit should be about the same size diameter as your LED Lenser. The bottom of the Lenser should almost fit in to the 3/8 side of the barb. If it doesn't then use your drill bit to bore the hole out on the barb. Do this a little at a time until you can work the lenser into the barb and get it full seated, or as far as it will go in. Once you have it fully seated remove the Lenser so we can work on the other side of the barb.

Next, see if your nylon barb 1/4" side will slide onto the 1/4" in fiberglass rod ( with a little bit of effort it should slip right on). If not you may have to bore out the barb with a drill bit to get the barb to slide over the rod.

If this all works out you are ready to use your acid brush to apply some glue to the rod and slide the barb on to the on to the rod. Only slide the barb on to the rod until the rod end is flush with the bottom side of the 3/8's side of the barb.

Next cut yourself a piece of your 3/8's heat shrink and put it over the 1/4 inch side of the barb. Then use your heat gun on the heat shrink. It should shrink down nice and tight. See my pics below for how it should look.

Step 4: Manufacture the Whip Holder

In this step you may have to look into your "Barney bag" or box. You have to have kids that watch Barney to get that quote.

As I pondered how to make the holder I came across an old towel rack I had in my "Barney box". I decided that I could cut off a piece of this towel rack and cut and wedge a short piece of wood inside then drill out the size if my fiberglass rod. Everything went just as I planned, and that almost never happens.

I also had to find a spot on the bike where I could mount it. I didn't feel like drilling into my son's (Mr. Rig it Jr.) bike. So I had to find someplace already accommodating. There is a hole on his bike just before the rear axle and worked like a charm See the pic).

Measure where you will place your holder and then mark where you will need to drill a hole for the bolt to go through.

Find a bolt that is neither to long or to short, but just right (this almost never happens either but it did this time).

Once you have your bolt you have assembled your whip holder and drilled out the correct size hole install it on the bike.

Lets got to the next step

Step 5: Test Fit

In this step we conduct final test fits of the whip into the whip holder and the Lenser into the barb.

Your whip/rod should have a snug fit into the holder. At this point you can put some glue in the holder and push the whip in for better securement. Or if you have a nice snug fit and you don't think the whip will fall out do put any glue in it. This is the preferable choice anyway because you can remove the whip anytime you want.

Next check the fit of the Lenser in to the barb. I suggest putting a tough of glue around the bottom of the Lenser and then install it in the barb. After that you can cut a piece of heat shrink place it over the barb and lower part of the lenser to secure it in. Then shrink the heat shrink tubing for a snug fit.

To replace the batteries in the Lenser you only need to cut off the heat shrink tubing and then remove the Lenser. It will come out easy enough, don't worry about the glue. you won't have to replace the batteries often at all they last a very long time. Then reinstall the same way as before.

Step 6: Test and Ride

At this point I called Mr. Rig it Jr. to take his bike for a test ride. I made a video, but it didn't come out that well, you can see the light though. (I will add the video soon) The video doesn't do it justice though. It works!

Using a tent pole which has a hollow core, a hole running up the length of the center, makes the the whip less rigid and in turn causes the pole to wag back and forth a little more than I would like.

I have made another using a solid core ATV whip and it works pretty darn good.

That's it you are all set to go and ride at night. Be safe and have fun.

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