Bamboo Bike Final Documentation

1.

For my semester long fabrication project I decided to build a bamboo bicycle frame. I started out by doing a lot of research on bamboo and its strength properties to see if bamboo bicycles were as reliable as people claimed them to be. I found out that bamboo have similar strength properties to aluminum, so I concluded using bamboo as tubing for a bike frame is perfectly reasonable.

Going into the fame design process I initially designed a mountain bike frame using Bike CAD Pro, but then because of availability of bamboo I had to change my frame design to a road frame.

The next problem I faced was figuring out how to join the bamboo tubes. Commercial bamboo bike frame builders use either internal or external carbon fiber or sometimes even metal lugs to hold the tubes together but I wanted to experiment with natural fibers, so I chose to use hemp. I ordered several hemp fabrics samples and did tests on which were strongest and which adhered best to the bamboo using epoxy, which was my adhesive of choice for this project. I chose to go with hemp canvass because it was more durable and because it was thicker soaked up the epoxy and held the tubes together the best.

I machined my own head tube and bottom bracket out of steel for my bamboo frame and purchased dropouts, which I had to modify slightly to work with my frame.

Before starting building the frame I had to first heat-treat all of my bamboo. To do this I first got most of the moisture out using a propane torch, then I bakes the tubes for an hour at 350ºF.

When building the frame I decided to use foam lugs to hold the tubes together while I raped them in epoxy impregnated hemp canvas. I was fortunate, the epoxy resin I used did not react chemically with the foam and eat away at it, it actually absorbed some of the epoxy providing a stronger bond.

2.

Testing will be done this summer when I return to California where I have the parts to finish building up the bike.

3.

The final status of the project as of now is a completed bamboo frame. As I said above I will test out the frame this summer back in California.

4.

If the frame does fail during testing I will have to figure out a better way to hold the tubes together. I imagine if the frame is going to break it will be at one of the tube junctures.

5.

N/A

6.

I did all the fabrication and documentation of the project.

7.

I originally was going to bet bamboo from a bamboo bike manufacturer in New York who grow and heat treat bamboo specifically to make bikes out of however that fell though so I had to order the largest diameter bamboo I could from a fencing company in New Jersey. I go the bamboo for my chain and seat stays from Triple Brooke Farms in Massachusetts.

Another problem I encountered was precision in frame alignment. There is no good way to align a bamboo frame.