Environmentally Friendly Rocket Bike.

Introduction: Environmentally Friendly Rocket Bike.

I woke up laughing from a dream . . . the dream of a bicycle being momentarily boosted by  a number of water bottle rockets, using only recycled materials, ( or at least not buying anything new.)

This may seem at first seem like a silly idea but like all good projects I learned a lot, pondered a lot and, above all else, had fun on a bicycle at the same time.

I did not know if it would work but finding out was going to be rewarding and other people also enjoyed the spectacle of the rocket bike..

Think of this like the first car or the first powered flight . . . they were rubbish . . but these humble beginnings led to the supercars and the supersonic aeroplanes that we know today.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: Instantly Humbled by My Own Ignorance.

I started by making a plywood box that held 9 x 2 litre bottles . . . I planned to have 9 inner tube bungs all being pulled out of pre-charged bottles by a static line.

(See the first photo.)

Behold its majesty and, potentially, frightening watery power . . .  

I then realised that the inner-tube bungs that I use for normal bottle rockets were not up to the job because they always leaked a little bit.

It was at  this point that I realised this was a day wasted and that this would not be not as easy as I thought .
I began to research into a reliable delayed release system.

Step 2: Researching a Delayed Research Mechanism.

There are many different systems around but the one that I liked the one that used only a Jubilee clip, some old pipe and some zip ties;it is very elegant and I believe that it's conception is attributed to Dave Lowe but some sites say Ian Clark.

This site was very informative:


The first picture is from this site.

Read on and it will be explained.

I needed a plumbing fitting.

My plumber friend gave me one but Asking for another 8 of them wasn't really an option.

If I ever get another 8 The dream will happen  but until then this is the first step.

Step 3: Time to Make.

Ok here is the fitting; it is  a compression fitting for 22mm pipe with and an end cap.

The pipe that is needed is 21.5mm - I had some handy because a cowboy plumber had used it in my boiler instead of 22mm and it leaked constantly; I asked the man who repaired it for the 21.5mm; who would have thought that it would be used for a major technological leap ?

So ;

Cut a valve from an inner tube.

Drill a hole in the end cap 7mm, just tight enough to allow the valve through.

Fit and tighten these parts together.

Fit this assembly onto the 21.5mm pipe.

Step 4: Zip Tie Time.

Use a jubilee clip to loosely attach about 6 zip ties to the 21.5mm pipe.
See photos for the principle; the ties will be adjusted later.

The tops of the zips ties ' clip '  around the neck of the bottle and hold it in place until lhe launch.

It doesn't really matter where you use the jubilee clip along as when the pipe is inserted into the bottle that the zip tie ends are in the correct position to hold the bottle in place. ( see photos.)

Step 5: Adding the Trigger Tube.

this is another piece of pipe that you will need.

I don't know where I got it but it is the perfect length and diameter.

I will measure it later; it is about 34mm diameter.

This slides over the 21.5mm pipe and the zip ties; it holds them in place.

Step 6: Adding the Powerhouse.

I used a 2 litre water bottle ( I couldn't wrestle the 3 litre White Lightning bottle off the guy in the park ).

The bottle should be a third filled with water (champagne gives slightly more lift , (except the 73 vintage; a terrible year for rockets)).

The cap has to be drilled out with a 22mm bit.

An o-ring is needed to seal the cap; anything around the 22mm size seems to do the job.

Ok Baby, the bottle is pushed onto to the 21.5mm pipe.

Adjust everything until the zip ties are in line with the neck lip of the bottle.

Now push the wider diameter pipe over the zip tie end ; this locks them in place all rosy like.

Step 7: The Plank.

For convenience I attached everything to a plank.

But I also added a little split block with a 22mm hole in it for the 21.5mm pipe.

This holds everything in place and also stops the pipe assembly being thrown into the face of an  litigious bystander.

Step 8: Adding the Trigger.

The trigger was just a length of , actually I am not sure what, but anything strong, long and light will do.
This was taped to the trigger pipe.

Step 9: The Event.

It's probably better to go to the video on the first page for the end result but here are some stills.

That's one spurt  for man but one giant gush for mankind.

Its been absorbing and fun.

Please vote for this Instructable if you have enjoyed  it.

Thank you

Step 10: UPDATE 2017 . . . This Guy Did It . . . ..


Hurricane Lasers Contest

Participated in the
Hurricane Lasers Contest

Bicycle Contest

Participated in the
Bicycle Contest

Be the First to Share


    • Backyard Contest

      Backyard Contest
    • First Time Author Contest

      First Time Author Contest
    • Silly Hats Speed Challenge

      Silly Hats Speed Challenge

    5 Discussions


    7 years ago on Introduction

    Cool build, you made it fun to read, the video was what sold me though :-D


    7 years ago on Introduction

    Don't know about how much rocket power you get, but that sure would work well to deter doggies, and drafters!


    Reply 7 years ago on Introduction

    You are not wrong.

    On the way to the Launch site I was severely tempted to release it onto innocent passers-by; just one litter-bug would have seen the trigger released.
    I ride too slow for drafters but that would be the best fun ever.

    Rocket power = negligible.


    7 years ago on Introduction

    Loved the video. Great job having fun and building something.


    Reply 7 years ago on Introduction

    At last , someone who enjoys the pathetically stupid projects.

    Thanks for the comment, Random23.