Loud Bike Horn (car Horn)-easy to Make




This is an actual car horn on a bicycle. Learn how to build it yourself!


Step 1: You Will Need

-the horn, I got a wolo maxi sound duel horns
-wire, I used 12 gage wire but it's up to you
-1/4 inch connectors and some crimpers
-battery, I used a standard 12v 7 amp but as long as it's over 5 amps, and 12 volts do what you please
-charger, I'm using my ex car charger but any one will do
-button for horn I got one at auto part store that has a horn emblem but any one should do
-mounting brackets I used mainly zip ties and big hose clamps

Step 2: Wiring

I'm not the best diagram drawer but this shows how to wire it all up, it's parallel. of course you should measure it and cut to the length you desire, and solder is not necessary but recommended. (Assuming you own a car hook it up to the car battery, to make sure it all works.)

Step 3: Mountin

This might be the hardest part because all bikes are different. I found mounting it in the triangle shaped area was the best for me but you might have a different style bike so this is the part where you get creative

Step 4: Tips

-Put tape under any thing metal that you mount so you don't scratch your bike
-use the horns ground plate to mount them
-the more power the louder it will get but don't go over 14v and 15 amps
-use common sense because most people get annoyed
-the wiring for he people who know its parallel
-give it a good shake before you take a ride to make sure they won't move
-the charger I use is a X1 ac plus
-if you have a water bottle keep it away from the electronics



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    12 Discussions


    2 years ago

    Looks like a great project. I was thinkning about putting this on my bike so I can get through the crowds on the way to school.


    4 years ago on Introduction

    Nice! I have done a couple of variations on this sort of thing with the same sort of horn. One I bolted onto the edge of a metal mesh basket, the other on a big homemade aluminium box which was mainly holding a massive spotlight. Both I have powered with NiMH cells, which isn't as heavy as lead acid. I buy 10x AA holders and fill these to get 12v. These horns are great.

    3 replies

    Reply 4 years ago on Introduction

    Yeah - this is with NiMH AA rechargables, which are 1.2 volts each - you can also get 12v off 8 AA throwaways.


    4 years ago

    Why not drill out your frame to hide/protect the wires?

    1 reply

    Reply 4 years ago

    I have a expensive bike that I might want to resell but that would be a good idea I hadent thought of that


    4 years ago on Introduction

    HA this is awesome! I'm sure it's super loud and gets everyone's attention.


    That looks great! I'm not so sure how that setup would hold up in the weather though, especially those connections with all the exposed metal. An enclosed box for the battery and the connectors might be a worthy upgrade. Either way, a car horn on a bike will certainly make drivers aware. Thanks for sharing.

    1 reply

    Reply 4 years ago on Introduction

    i live in the bay area and it has only rained 2 times in the last 5-6 months and i try to stay out of the rain on a bike, but that would also be a good visual que, thx for the suggestion @gravityisweek