Extremely Loud Train Horn Bicycle





Introduction: Extremely Loud Train Horn Bicycle

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So you want to be loud? You want to make a statement? You want to scare the crap out people? A train horn will do the trick. Do you want to stand out in the process? Than a bike with a train horn attached will defiantly do the trick! 

So you may be asking yourself why would you possibly attach a train horn to a bike? Well the first reason is that I currently do not own an automobile, so this is the best that I can do. The second reason is that it just so unexpected and fun to use. Have you ever heard a train horn in the middle of the street and seen that it was coming from a bike? I didn't think so.

To start off, let me explain some things:
     1. The reason why there is a portable air tank on the back of my bike is that hooking up an air horn to an air tank is much louder than attaching an air horn with the provided compressor. 
     2. The horn I used can be heard from over half a mile away. Although this is not as loud as an actual train horn, it does the job.
     3. The total cost of the project varies. If you happen to already own all of the materials, it will cost nothing. If you own none of the   materials, it could cost over $200 to construct.
     4. It takes about 30 minutes to construct.
     5. This is an extremely fun way to scare/prank innocent pedestrians, although it should be used respectively. Blowing it near traffic is NOT a good idea!

Step 1: The Bike

The most important part of this instructable is of course the bike that your going to be using. While you could use any bike for this project, a cruser is 100% recommended. The reason why I recommend a cruser is that most of them include luggage racks on the back. This luggage rack is vital because this is where you will place your air tank.

* If you do not have a bike with a luggage rack, you could build one using either wood, metal scraps, or even PVC pipes. 
Some nice instructables on building bike luggage racks...
                carpespasm's instructable
                darlingtom's instructable
                graphicsman's instructable

Step 2: Materials Used

Materials Used:
    - A 10-gallon air tank. (Any tank will work)
    - Dual trumpet air horn. (Any large horn will work)
    - 2 bungee cords (Any strap will do)
    - Duct tape
    - Air blow gun attachment for air tank
    - 4 foot long 1/2 inch thick hose (running from the air tank to the horn. Any length of hose will do)

Optional Materials:
    - An old towel (so the air tank doesn't scratch the bike luggage rack)
    - A large hose clamp (for placement of the horn)

    Air Horn-   Any where from $15 to $200 on Amazon. The one i used is HERE
    Air Tank- Any where from $30 to $60. I used some old tank. You can buy them HERE
   Bungee Cords/ Straps- Very cheap @ any local hardware store. About $5 each.
   Air gun attachment, duct tape, hose, and large hose clamp- Very cheap @ any hardware store.

Step 3: Attaching Materials to the Bike

Now that you have your bike ready and your materials on hand, it is time to construct it all. 

             Before Attaching the Materials:
1. Fill up the air tank with air. Over half a tank is recommended.
2. Make sure that your portable air tank is attached to a piece of 1/2 inch thick hose. The length of the hose is up to you.

             Steps To Attaching The Materials:
1. If you don't want to scratch your luggage rack on your bike, place a towel down.
2. Set your air tank on top of the luggage rack.
3. Take your bungee cord or strap and wrap it around the air tank and the frame of the bike. (Be sure to wrap it around a secure spot on your bike frame)!
4. Take your other bungee cord or strap and wrap it around a different spot on the bike frame and the air tank. (Attaching any other cords/straps for extra support is recommended but optional).
5. Take your hose running from the air tank and strap it on the frame of the bike using (duct tape) until it reaches the handlebars on the bike. 
6. Try to place the blow gun attachment at a comfortable position on the handlebar. Strap it down with duct tape. 
7. Attach the blow gun attachment at the end of the hose to the hose from the air horn.
8. Position the horn on the handlebar. This is where the hose clamp may come in handy. Luckily this bike has a cup holder to position the horn on so a hose clamp is unnecessary. 

Step 4: Test Drive

You are finished! Now that wasn't so hard, was it? To blow the horn, simply make sure that the air tank valve is open and push down the lever on the blow gun attachment.

Now that your amazing project is completed, it is recommended for pranks, scares, showing off, and just having fun. The possibilities are all up to you! 

Please comment and favorite if you like it! This is my first instructable so please follow me for cool new ideas. Oh and one last note, if you see the police, i DON'T recommended blowing the horn. 



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    awesome! I have Ontario northland train horns, so I will mount them on my pickup truck, instead of the bike. All mount them in the truckbed so no one will think that I have train horns in my truck bed. All also use a bigger compreser.

    that is utterly ridiculous and want it on my bike

    If the bike is tipped over or crashed and the tank gets cracked or the valve breaks off, what are some of the safety concerns for having a air tank strapped so close to a person. Don't want a Wild E Coyote incident happening with the tank. I have hear of large high pressure tanks falling over and the valve breaking and the tank getting shot through cinder block wall and wrecking cars in the parking lot. Old retired dude told me that story.


    Cool project!

    But I'm afraid I'm gonna have to jump on the safety bandwagon here, but I'll jump off pretty quick.

    You say the tank is old. When compressed air is cooled, the humidity in the air condenses and pools up in the bottom of the tank. The tank is probably fairly rusty on the inside, especially where it's welded together. Assuming the tank is about 8" diameter, you have roughly 50 square inches in the welded-on ends of the tank. Assuming a modest 100 PSI (you didn't say what pressure you fill it to, or I missed that part), that's 5000 pounds pressing against it. IF the weld were to break simultaneously all the way around, and someone got in the way, they would be hurt, probably severely. It's unlikely, but I like to play it safe... when there is no fun lost in doing so :)

    I DON'T suggest doing the following (it's probably considered dangerous or something..., I want no liability here):
    What I do to pressure test an old tank is duct tape the pressure relief valve so it doesn't open at the pressure it should. Somewhere on the tank it will have a maximum pressure and burst pressure stamped into the metal. I fill the tank to 20-30 PSI below the burst pressure (or as high as my air compressor goes, depending what the rating is) AFTER placing it in a steel box. I fill it while monitoring a second pressure gauge outside the steel box. If it holds up, I use the tank for another year. I had one break once, and it put a good sized dent in the side of the 1/8" thick stainless steel tool box in the bed of my truck. But it was also about 14" in diameter and burst somewhere around 140 PSI, so a lot more force.

    Hmm good observation, however I would have to say that there's a much better chance of falling off your bike and getting seriously injured, then the tank exploding and seriously injuring you.

    While this is a really neat idea in theory, I have to add another caveat to this. If you are anywhere near traffic, don't use it. I don't think the owners of these things realize how startling they are to the unsuspecting motorist/pedestrian. I have a neighbor who has one on his truck, and I've seen dogs and cats dart into the street, cars hit the curb and go into a lawn, and several almost-collisions when he's blown his horn. People will most certainly slam on their brakes, swerve (hopefully not into your bike), and do all other sorts of unexpected things when you blow this horn.

    If you do decide to use it, I hope you have good insurance.

    Having been personally run off the road, and chased by countless dogs, I would not hesitate to use this, I will be the first to buy one when they are miniaturized and I will laugh when the guy that was about to kill me "is startled". I love this thing.

    Not as loud, but you can buy a miniaturized one: