Hey, here is my 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.