My bamboo fixie
 

This is my first attempt of building a fixie out of bamboo and a chopped up old steel frame. I never really finished this project because of some design flaws, however I'm in the process of building a new one now, in my opinion much nicer. But I decided to post these pics for some feedback.

First step: chop the bike:
http://img.photobucket.com/albums/v2...ttachment5.jpg

Second step: fit and spraypaint:
http://img.photobucket.com/albums/v2...ttachment4.jpg

Third ste:p figure out a way to attach bamboo to frame, I used 5 minute epoxy and homemade pins. It proved to be a real stable connection:
http://img.photobucket.com/albums/v2...ttachment3.jpg

Fourth step: mock up and extras, I made the bamboo seat post (not a good idea) and bamboo handlebars:
http://img.photobucket.com/albums/v2...ttachment1.jpg

Fifth step: semi finished fixie:
http://img.photobucket.com/albums/v2...Attachment.jpg

I actually test road this bike and it actually worked. I just didn't like a few things about the frame. And by the way I am a mechanical engineer and I did do some calculations. Don't try this at home:)

Looks super sexy in my opinion :D:D:D:love:

I would totally suggest thinking about bamboo seatstays as the backhalf of your bikes lacks bamboo in my opinion :lol:

Or at least replace the rear brake bridge with bamboo :D

thats the plan for my next one, i'm going to do the down tube, bottom tube and seat stays in bamboo. I am going to leave the top tube alone, it has alot of stress going through it.

You should really think out the bamboo seat stays.... it would totally suck if you had catastrophic frame failure with the bike almost complete.... (think about the brake bridge instead :thumb: )

Very interesting. Do you know the mechanical properties of bamboo? How does it fare in torsion? FYI, I'm a retired structural engineer, so this sort of thing interests me. Please keep posting your progress.

I feel like bamboo does better with compression type of forces versus torsion. my biggest concernig is picking bamboo that is thick walled and in good condition. the bamboo also needs to be completely dried out and crack free. In this build a small crack started to invade the top tube, thus the reason I am starting over with a new design.

Also, read up on fire-hardening the bamboo. Bamboo gains strength if it's been heated in fire / with a torch, so read up on how to do that properly.

http://www.npr.org/templates/story/s...ryId=121628758

NPR ran that story a few weeks about about some bamboo bike builders in Brooklyn. worth a look.

Is bamboo fibrous? Lengthwise fibers? I would image it's stronger in tension.

TejanoTrackie, ever run SAP models or anything on a bike frame? Would be kinda cool...

based on how you are making your frame, this tutorial may be of some help: http://www.instructables.com/id/Bamboo-Bike-2/

That's interesting, and definitely a smart way to go about making a "bamboo"-bike without an excessive amount of work, but to be honest I would be scared to ride this bike.

to be honest I am little scaried to ride it. i'm just going to take it slow. i'll test it out in singlespeed mode first. safety first safety last safety always.

Awesome project! Good luck

i kinda cringed at the first picture. The thought of chopping my bike scares the crap out of me.
But those last few pictures looks awesome. Great job! Does it feel a lot different than a steel bike?

No, but I've done some simple hand calcs, and from what I can tell the downtube carries the lion's share of torsion, which is why modern frames tend to have massive oversized downtubes. Under just the weight of the rider without any force on the pedals the entire frame acts like a truss with all the members in either tension or compression. Torsion and out-of-plane bending are introduced when power is applied at the pedals due to the Q-factor. IMO, the downtube and chainstays would better remain as steel, but the rest could still be made with bamboo. Of course, if the seatube is bamboo, this could be a problem with seatpost fitup.

I hope you don't kill yourself trying to ride it.

I posted my bamboo fixie on the framebuilding forum. You really should chop it up completely and make it all bamboo. I would recommend using larger bamboo and inserting the metal into the bamboo and then wrapping the joints.
The exception is that I would insert the bamboo chainstays into the chopped off metal stays.

As long as you build it right I wouldn't be scared.. some people built a triple tandem out of bamboo and road across the country with no problems.

Here is a sneak peak of my version 2.0

http://img.photobucket.com/albums/v2...tachment-2.jpg

I'm still looking at other bamboo options. I like the look of the thinner bamboo. The ones I choose were heat treated and thick walled.

Well aside from workmanship and traffic accidents... bamboo is a very flexy and not brittle (unless weathered); heck my loaded longboard is bamboo and it withstands my longboarding abuse...... and if bamboo does fail, it doesn't fail epically like how metal does, bamboo would just splinter mildly while remaining intact; he might even be able to ride it back home after a failure of a bamboo tube...

OP you might want to find something to protect that bamboo from the elements if arent using anything..... I recommend coats of varnish and then polyurethane

Nice, but one question, why those drop outs, you could have gotten the track drops.

I do know a bit about bamboo, and a little about metal, I also know a little about joining the two, thats why I hope he doesn't kill himself riding it.

frames with track drops are expensive... even the older track frames.....

that way if he F's up he can easily afford to get another expendable horizontal dropout frame. ;)

since this is my first experience on this type of project, I didnt feel right dropping $250 on a nice track frame. If this one works out, I might. Here are two more pics of what I got going so far with the new build.

http://img.photobucket.com/albums/v2...ymatty/bb1.jpg

This one shows the joints. The bamboo has been epoxied to the inside of the luggs. Of course everything was sanded down and roughed up. I also used epoxy putty on the outside of the connection (that is the white clay looking material). It has been shaped and sanded. The frame and the bamboo is also drilled out for a 1/4" pin to add an extra safety guard. Also the ends of the bamboo were capped to help prevent splitting. The pin will be epoxied and bolted into place.

http://img.photobucket.com/albums/v2...ymatty/bb2.jpg

by the way thanks for everyones safety concerns. this is just a project of mine. if it doesn't feel right, i'm not going to ride it. I also switched the project from a fixie to a singlespeed. A little safer.

True if you decide to go that route. But you can buy the parts needed from places.