Introduction: How to Build a Great Big Tall Bike.
I was given lots of parts of bicycles and as as none of them were any good or complete I decided to uses up all the parts that I could to make something beautiful.
I used two mountain bike frames and an extra sets of forks ( three in total) and a bmx back wheel.
I made it up as I went along and it was lots of fun.
I used an arc welder (stick welder) which is not ideal for bike frames but if you don't mind burning a few holes into the frames then it is ok; a Mig or acetylene welder would be easy peasy.
My welding is not so good so I jumped around on the frame before riding the bike to make sure that it was safe.
It rides like a dream.
The first step shows everything in an animation form ( this is also in the film) and then the subsequent steps show more detail.
Here is the video ( which is essentially someone riding the bike around in circles for 1 minute and eight seconds); enjoy.
Step 1:
If you were too busy to watch the film then here is a quick animation.
Step 2: The Forks.
Firstly I took the front wheel off.
I took my second pair of forks ( No. 2) and cut them top and bottom as shown, as shown.
I cut the drop-out ends off the original forks.
I slid the No.2 forks onto the original forks and welded them on.
I took another set of forks (No.3) and cut them at the top and slid and welded them onto fork No.2.
I thought that it would be a good idea to put a brace across the forks for strength.
Unfortunately I had no metal at all; I used the front chainset from frame number 2 and welded it across; it looks rather stylish.
Step 3: The Back Part of the Frame.
I took another frame( frame 2 ) and cut it in the places shown; cutting away the seat tube, down tube and cross bar, leaving me the seat and chain stays and bottom bracket.
The frame 2 was positioned in the original frame; the bottom bracket between the rear drop-outs and the seat stays nestled around the bottom bracket.
I ran a bolt through frame 2's bottom bracket to hold it tight for welding.
I persuaded frame 2's seat stays to curve around the original frame's bottom bracket with a hammer.
It was then welded at those points.
Step 4: Other Easy Bits.
The original front wheel was put back on and a 20" bmx wheel on the rear.
The rear de-railer was removed and the chain was lengthened using the chain from frame 2.
The front de-railer was kept as a rudimentary chain guard.
I now strive to, however stupid the bike, to have at least one good working brake.
I removed the cantilever brake arms from the original forks and put them onto No.3 forks.
These were connected to the brake lever by using a rear inner brake cable which is longer than a standard front one,( the outer cable length is not affected.)
This would be as easy with V-brakes ( but you would have to change both the inner and outer cable for long ones).
This project was a huge amount fun and many people have ridden it.
It's very easy to ride although, as you may have seen, my friend did an impression of a sack of potatoes being thrown down the stairs when she tried; she was unharmed apart from a sore leg.
Happy riding.

Participated in the
Bike Contest
16 Comments
8 years ago on Step 4
Thanks Crazypj,
Check out this site maybe.
http://www.atomiczombie.com/
kind regards
FOH
9 years ago on Step 4
What a great idea, I have a few scrap frames from kids BMX bikes. They are way too small to be any use, but, some cutting and welding could make something 'weird'
10 years ago on Introduction
Love the animation - you ought to write another instructable on how you made it.
Reply 10 years ago on Introduction
Thank you Kiteman; it's just stop frame animation.
Reply 10 years ago on Introduction
Still, I'm sure it would be popular.
Reply 10 years ago on Introduction
+1. Absolutely. Show us how you did it.
Reply 10 years ago on Introduction
The animation is very effective.
Reply 10 years ago on Introduction
Thanks man.
10 years ago
cool bike like the design looks like lots of fun
Reply 10 years ago on Introduction
Thanks GreenHatNRG, it's a scream to ride.
10 years ago on Introduction
I,ve been trying to work out a cool tall bike design to use up some of my old bike parts. I think this might be it. Great work and great i'ble. Thanks.
Reply 10 years ago on Introduction
Thanks; post up a picture if you do.
10 years ago on Introduction
Clever and original design solution.
Reply 10 years ago on Introduction
Hola Rimar2000,
Gracias por los lindos comentarios.
10 years ago on Introduction
Very nice, and I enjoyed the video a lot. It was the perfect balance of showing the bike clearly and fun!
Reply 10 years ago on Introduction
Dear Unigamer,
Thanks for the feedback, I'm glad that you liked it.