Welding

Wobble Bike

posted Apr 2, 2015, 3:16 PM by Neil Caulfield   [ updated Jul 7, 2015, 1:00 AM ]

Date: Summer 2013 (Painting and customization still in progress, but actual build already complete)
Cost to build: Made from acquired scrap bicycles. 
Time to build: 3 hours (bare essentials to ride it, longer for paint and customization)
Original inspiration: Instructables Post

This project began in June of 2013 and was quickly made rideable the same evening. This project involves the sacrifice of two undesirable bicycles to make one very desirable bicycle that grabs the attention of others again and again. The purpose of the second bicycle is mainly to create a second hinge point in the bike, but does make up part of the new frame. The handset and part of the fork are welded to the primary bike frame at the seat post, and the other end attached to the front of the primary bike frame. (See the instructable for details on the exact configuration I used, or the picture below).

The red frame was given to me for free with a craigslist purchase of a complete bike. The black frame was from a beach cruiser purchased new in the late 1990s but unused since the early 2000's.

See it in action HERE. See a better video embedded below!

In late August 2014, I disassembled the bike to paint it fluorescent orange and pink, to give the startling effect of a bike that may have lost its mind more apparent. I also plan to buy some yellow tires to go with the other colors. With the weather turning colder I decided to hold off until the following summer to complete and reassemble the project. Many of the bearings had to be pulled out so they will need replacement, but the hinge mechanism is permanent due to the nature of welding, so the main structure remains unaffected.

This project is fairly easy, even if you have a basic understanding of welding. Just be sure to practice on the unused portions of the bike to confirm your settings are ideal for the tubing you are working with. If you do build this, be sure to check your welds and make sure they are structurally sound before you ride it. I will not be responsible if you impale yourself with a jagged piece of poorly welded metal! 

Riding it is not exciting, unless you want it to be. The bike will not try to flex, fall over, or fold on you while it is in motion as long as you hold the handlebars. To move the hinge, pull the handlebar to the side and pull back while keeping the front wheel straight. You can "drift" the bike by turning the back wheel but keeping the front wheel as straight as possible or by countering your drift by pulling the wheel parallel with the other. 

People love this thing, especially when it catches them off guard as the rider flies sideways around an intersection at the beach. On main roadways, dodging manhole covers and potholes is as easy as swinging your seat and handlebars in opposite directions; and your center of gravity and average velocity across two axes does not change much. Its easy enough to ride that people can try to ride it without having to worry too much.

In the future I am considering a build with two seats, but I am still trying to determine how that would work. That design may involve four hinges and three wheels. At the very least it would be interesting to have a pointless third wheel chasing along the original single seat. So far I have a three wheeled, two seat, four hinge design in mind, but whether it will ride at all is unknown. 

It is finally done! I finished it just in time for the peak of the 2015 summer season! Painting is completed and I have also added yellow tires and yellow handlebars to go along with the theme. Check out a brief but detailed demo video below!


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