It gives the option of no sound or variable degrees of volume and timbre, controlled from the handlebar.
At the push of a thumb you can instantly create the motorbike effect and at the pull of a finger you can stop it instantly.
It is great for grown ups who want to be silly but don't want to be seen being so, or for your children so that they don't drive you crazy with continual noise.
It's an idea that I couldn't get out of my head until I constructed it.
I made it for my friend's son but first Katarina and I had fun test riding it on my bike.
( As you can see in the video, Katarina turns off the sound when she is passing a group of people; be warned, it is a bit noisy ).
It also works like a bell, a blip on the throttle and the pedestrians will move out of your way.
It's an entirely original idea, for obvious reasons; This is a very niche item.
Step 1: The start.
I thought about complex helical screws, or maybe using a single brake arm bolted onto the forks . . . but then the idea hit me; a rear de-railer from a bike has the perfect linear movement that is necessary for this project.
This became my starting point and everything that you read is the process of trial and error that led to the finished project.
The gear lever became the ' throttle '; giving a variable amount volume by pushing the card, held by the de-railer into the spokes.