# Bamboo bike



## bboyuseless (Feb 21, 2011)

I am building a bamboo full suspension, all mountain mtb. All the designs are completed and I'm being a little stingy with information in regards to that as this is my first time posting anything of real substance on any internet source. Let me know what you guys think.

http://bambusabicycletta.tumblr.com/

This blog is meant as a process book/portfolio piece so it will be linear and have small day to day updates.


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## Pimpride (Nov 14, 2005)

*Looks cool*

I like it. Looks super cool, I like the 'hemp' lugs. Did you you coat the lugs or is it just tightly wrapped? I'm wondering how it will end up.


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## bboyuseless (Feb 21, 2011)

I bought the thinnest hemp cord possible. Then I split it in half manually so It was about half a millimeter wide maybe less. Then I coated the bamboo with wet epoxy to saturate underneath the cord, wrapped the cord tightly in about 3 or 4 layers, re-wetted the cord once it was on to ensure that it was completely saturated (this is very important) then wrapped it in vinyl tape in order to compress it. I finished it with heat lamps to increase temperature to ensure a proper cure then the real work started. 

I sanded it down with 80-120 grit sandpaper to shape the lug, I also used a rasp but sparingly as this temped to "rip" the fibers. Sanding was very difficult because sanding rope basically makes the lug into a shag carpet so the cord being wrapped needs to be as thin, i repeat as thin as possible but still wound in some fashion together in order to retain the structural integrity of hemp (seen naturally when rope is weaved it has a much higher breaking point than when rope is just a bundle of straight fibers) 

I am going to construct a lug with multiple layers, a stronger epoxy (i used 5 minute crap just for the test, I plan to use west systems 20 minute for the real deal) and a little surprise which i don't want to reveal unless I'm absolutely certain it works. 

Oh yea, then after I finished form sanding and aesthetic sanding I coated the surface with a very very thin layer of epoxy, this eliminates the shag carpet effect.


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## davesauvageau (Jan 8, 2010)

I like the look of the hemp lug. A lot of people do carbon lugs that look bulky and ugly. Yours are very nicely shaped and are a more natural look than pitch black carbon. Good job, I can't wait to see more!


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## Cayenne_Pepa (Dec 18, 2007)

Nice! Can Bamboo be painted, or is it best to leave it natural?


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## bboyuseless (Feb 21, 2011)

It can be painted, i mean it is wood afterall and wood can be painted. But why cover up the surface of such a beautiful organic structure crafted by nature?? 

I'm gonna clearcoat mine to make it waterproof.


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## bigbamboo (Mar 25, 2011)

For a clear finish you might try using Varathane.

I am going to experiment with this myself, the people who make bamboo fly-rods use it.

I think it is much easier to work with than epoxy based finishes, although it probably requires multiple coats to get a durable finish.


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## Drew Diller (Jan 4, 2010)

davesauvageau said:


> I like the look of the hemp lug. A lot of people do carbon lugs that look bulky and ugly. Yours are very nicely shaped and are a more natural look than pitch black carbon. Good job, I can't wait to see more!


I agree. I'm in the middle of a bamboo bike myself, and am using carbon tow. It's lumpy. I'm going to try to take a bunch of burnt up firewood (mostly carbon), mixing it into an epoxy paste, and using it as a filler.

It'll still be black, but it won't look so... eletrical tape ish.


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## lewiscomposites (Sep 27, 2010)

Drew Diller said:


> I agree. I'm in the middle of a bamboo bike myself, and am using carbon tow. It's lumpy. I'm going to try to take a bunch of burnt up firewood (mostly carbon), mixing it into an epoxy paste, and using it as a filler.
> 
> It'll still be black, but it won't look so... eletrical tape ish.


Don't use burnt up firewood and epoxy as a filler. If you've got carbon tow already, just cut up small pieces of carbon and mix that in with epoxy to create a filler. Then sand smooth once it's hardened. I generally wrap my lugs and then vacuum form for even greater strength. Here's the head tube on my bamboo track frame built with a mix of 3k weave and 50k tow.


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## spokeywheeler (Dec 1, 2006)

I used a water based clear polyurethane. I brushed three coats on by hand. Would be more consistent if sprayed on but you have to get pretty close to see any brush marks. The finish has held up great for 2 plus years, and is easy to clean.


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## wizzer16 (Sep 9, 2010)

I really like the way bamboo bikes look and yours is looking very clean. Not to pick on you or anything but i noticed you were using a drill chuck for that endmill. regardless the frame is looking sweet.


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## dbohemian (Mar 25, 2007)

lewiscomposites said:


> Don't use burnt up firewood and epoxy as a filler. Here's the head tube on my bamboo track frame built with a mix of 3k weave and 50k tow.
> 
> View attachment 604981


Hey, someone needs to make this a sticky because I just think I wet myself.....Would anyone ever have thought that one could somehow include in the discussion of framebuilding, burnt firewood filler and "bamboo track frames" in the same post ....Realty is stranger than fiction....


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## TimT (Jan 1, 2004)

Looking at your pictures your using a drill chuck to hold an end mill. Not good. A drill chuck is not designed for side loads and can cause chatter. I don't care how tight you get it. I noticed by the chips in your picture that your taking very small cuts. Try using a collet. its safer and you can take bigger cuts with way less chatter.

Tim


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## bboyuseless (Feb 21, 2011)

wow, I just noticed that too. I learned to side mill properly with a collet too. It just completely slipped my mind. 
I actually ran into a really big problem. They kicked me out of the shop for no reason. literally. All that was stated was policy. you can't work here because i said so. So, probobly wont even be able to correct my mistake. I was so preoccupied with fixing their machine that the collet thing slipped my mind. Thank you, I have a collet at my disposal. If i get back into the shop, I will correct my mistake.


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## cbchess (Dec 20, 2003)

I've been researching Bamboo Bikes for a few months now and I am almost ready to start construction.

I've harvested some local Bamboo which seems very promising to use for my frame. I've dried my bamboo in two ways. First is the hand held propane soldering torch. Second is my gas grill. I did one test on the grill and it burned my test stick right up. So I covered the grill in heavy duty aluminum and a heavy duty industrial baking pan turned upside down to make more of an oven.
I heated to about 375 degrees for and hour or so until I got a color change. This involved lots of checking and flipping and rotating the short poles to get a uniform "cook".
After both processes I have dried the poles further naturally by vertically storing them in a wooden structure for about 5 weeks now.

I've sourced some metal bits from local frame builders for my head tube and BB and rear drop outs.
I ordered some Hexel Carbon tow (12k) and just got a shipment of super strong boat building/ aerospace epoxy.

I will be using a much cruder jig something like this:


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## bboyuseless (Feb 21, 2011)

1: what kind of epoxy are you using? I am using West systems 105/206 and am attempting to compare and contrast brands. I'd be interested in hearing of your choice.

2: They sell these shish kebob stakes that attach to a motor and hook on to the side of the grill and rotate while the lid is closed, I can imagine that being very useful for heat treating the bamboo on an aluminum covered grill if you end up doing it again. It would make uniform heating very very easy.


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## cbchess (Dec 20, 2003)

I am using AeroMarine products epoxy resin
300 resin with the 11 hardner - this is supposed to be their strongest mix. I considered going with the non-blush 300/21 mix but the 300/11 mix is rated at a higher strength

Specifications: Viscosity: 3000cps maximum
Color: Clear Amber
Work life: 45-60 [email protected]
Cure time: 24 [email protected]
Shear strength: 2500psi
Tensile Strength 8000 psi
Flexural strength: 12,800psi
Modulus of elasticity: 5.7 x 106

http://www.aeromarineproducts.com/


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## cbchess (Dec 20, 2003)

this is the specs for west system

....................................... 105/205 --------105/206
Tensile Strength (PSI) ....... 7,846.........	7,320
Tensile Elongation (%)..............	3.4----------	4.5
Tensile Modulus (PSI) ------------4.08E+05-----4.60E+05
Flexural Strength (PSI)--------------	14,112------	11,810
Flexural Modulus (PSI)-------------	4.61E+05-	4.50E+05



You can see the aeromarie is a bit higher across the board especiall Vs the 105/206 mix. the 105/205 has slighly higher Flex strength at 14,112 psi but I think I'll be safe at 12,800psi

the big plus is I got a half gallon of resin and hardner for $26 bucks
sorry for all the dots and dashes tring to get everything to line up


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## Freddy Salgado (Jun 4, 2009)

Cool to see someone pushing the envelope with this material:thumbsup: Are you experimenting with new suspension design? Been beating I drive proto for about 3yrs and still ticking, need to get around to building rear end for it sometime.



bboyuseless said:


> I am building a bamboo full suspension, all mountain mtb. All the designs are completed and I'm being a little stingy with information in regards to that as this is my first time posting anything of real substance on any internet source. Let me know what you guys think.
> 
> http://bambusabicycletta.tumblr.com/
> 
> This blog is meant as a process book/portfolio piece so it will be linear and have small day to day updates.


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## bboyuseless (Feb 21, 2011)

Suspension wise, It is very similar to the one you have there but will be slightly different. I don't want to reveal secrets that I haven't personally seen done on or off the internet but I am building the rear triangle out of bamboo which will be a project. I've got a few tricks up my sleeve. Production should start soon. I've ran into a few snags though....

Mainly related to people. Dealing with people is the hardest thing about this project (and life for that matter)


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## bboyuseless (Feb 21, 2011)

There are alot of new pictures up on the blog for people to check out if anyone is curious on procedures or just wants something to look at.

Does anyone know anything about "smoking bamboo?" I know calfee advertises their bamboo bikes as being heat treated and "smoked." Their frames have a very distinct and very uniform smooth redish finish. Anyone know anything about this?

http://calfee.myshopify.com/collections/frontpage/products/bamboo-frame


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## Freddy Salgado (Jun 4, 2009)

I dont think we will ever know how or what Craig does to make those beautiful works of art, thats what makes it a Calfee. There is enough info out there to come close to the process Calfee uses, but we will never know exact recipe. The beauty of working with this material is you can come up with your own recipe & still make solid rig using general info on drying bamboo. Not many comercial bamboo bike builders out there & the good ones tight lipped about there process.
Sachs, Vanilla, Bohemian, guys like this spend so much time & effort perfecting there craft, wouldnt be surprised if they have tricks "up the sleave" they dont want other builders to no about.
Half the fun working with bamboo long enough is making your own discoverys, you are officially a bamboo bike pioneer 



bboyuseless said:


> There are alot of new pictures up on the blog for people to check out if anyone is curious on procedures or just wants something to look at.
> 
> Does anyone know anything about "smoking bamboo?" I know calfee advertises their bamboo bikes as being heat treated and "smoked." Their frames have a very distinct and very uniform smooth redish finish. Anyone know anything about this?
> 
> http://calfee.myshopify.com/collections/frontpage/products/bamboo-frame


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## cbchess (Dec 20, 2003)

It could be as simple as a red woodstain rubbed in as a finsh coat.


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## cbchess (Dec 20, 2003)

oh hey what is your secret wepon? a small machined piece of metal to help align the angle?


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## cbchess (Dec 20, 2003)

I think you could bend bamboo much easier when it was green and then heat treat it with a hand held propane torch to "set it" into the curve.


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## bboyuseless (Feb 21, 2011)

yea. I think the main problem why the heat bending failed was because I used a medium diameter tubing for the experiment and not a smaller diameter which wouldve been easier. That's all the extra I had though as I cut my own bamboo instead of buying from a source. 

The secret weapon is not that although It does very much look like that in the image.

I also tried stains and for some reason, even the darkest, darkest stain does not penetrate bamboo under any circumstances. I don't really know why honestly. Anyone know?


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## cbchess (Dec 20, 2003)

probably need to sand the outer layer off to stain it - it would repel the stain just like it repels epoxy.


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## cbchess (Dec 20, 2003)

or it could be a stain and finish (like polyurethane) mixed together - I've seen it done for hardwood floors


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## bboyuseless (Feb 21, 2011)

yea tried both on a test piece of dried, fresh and heat treated bamboo. Nothing worked.


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## Drew Diller (Jan 4, 2010)

In terms of bent/curved bamboo, I think it's telling that Calfee is using bonsai style controlled growth to achieve non-straight poles. Bamboo is a composite, it would be somewhat like expecting to be able to permanently bend a straight carbon fiber tube.

I'm not bagging on your choice of material at all. I really like your lugs.


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## Freddy Salgado (Jun 4, 2009)

Here is a good video on how to bend bamboo, 



. I have tried this method and its alot harder than it looks. Packing the tube with sand so that it has no voids inside bamboo tube is very important, & quenching the tube with cool water so it keeps the bend you are after. Once you lock in radius let tube finish drying by air, any where from 4mo to a year pending on climate in your neck of the woods. 
Your lugs are looking very clean & tidy.


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## Deru (Jan 4, 2008)

bboyuseless said:


> There are alot of new pictures up on the blog for people to check out if anyone is curious on procedures or just wants something to look at.
> 
> Does anyone know anything about "smoking bamboo?" I know calfee advertises their bamboo bikes as being heat treated and "smoked." Their frames have a very distinct and very uniform smooth redish finish. Anyone know anything about this?
> 
> https://calfee.myshopify.com/collections/frontpage/products/bamboo-frame


I'm from Japan, and building some bamboo bikes too. In Japan exist many companies that treated the bamboo in many methods.


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## Deru (Jan 4, 2008)

Carbonized bamboo
http://www.yamagata-kanryuchiku.com/english/index.html


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## bboyuseless (Feb 21, 2011)

wow, Deru, I cannot thank you enough for this information. If anyone has any information on smoking or carbonizing bamboo at home or on a small scale without a 6 meter kiln it would be greatly appreciated.


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## Deru (Jan 4, 2008)

Homemade carbonized bamboo it is so dificult, and expensive.
Homemade good treated bamboo it is so hard to get. Almost nice companies working with bamboo has 100 years. There are many ways to get a good treated bamboo, some companies use autoclave, because is faster I think.
Carbonized, boiled and water immersion bamboo takes at least 6 months to stabilize.
Look this page:

http://www.navaching.com/shaku/crack.html


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## Freddy Salgado (Jun 4, 2009)

Wow Deru, your bike tubes are beautiful. The shakuhachi flute is by far the most impresive item I have seen made by bamboo & testimony to the durability of bamboo material. 
Winter here in NZ so will have my fire pumping for next few months, will toss in some bamboo tubes in chiminy to have a go at carbonizing some bamboo. The sights you pasted are best I have come across so far.
We have our fair share of earthquakes in New Zealand but nothing like what happened in Japan, wish you all the best and speedy recovery thanks for taking time to chime in Deru. If anyone wants to pool info on bamboo bikes we started a fb page called bamboo bike riders, its general independent info on natural fiber bikes.



Deru said:


> Homemade carbonized bamboo it is so dificult, and expensive.
> Homemade good treated bamboo it is so hard to get. Almost nice companies working with bamboo has 100 years. There are many ways to get a good treated bamboo, some companies use autoclave, because is faster I think.
> Carbonized, boiled and water immersion bamboo takes at least 6 months to stabilize.
> Look this page:
> ...


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## Drew Diller (Jan 4, 2010)

Been following your blog, but there hasn't been an update in a bit. How are things going?


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## bboyuseless (Feb 21, 2011)

There are big things in the works and there will be TONS of photos coming up very soon but I have been right in the middle of a move and working two jobs so its been slow comings. Come Monday there will be a plethora of updates.


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## bboyuseless (Feb 21, 2011)

New material is posted up on the blog. I apologize for the irregularity of posts. The times are difficult these days but I am determined to finish the process. Let me know what everyone thinks so far and if this is anything that they have seen elsewhere. I would like to know if people think this is new and interesting or if it is the same old stuff they've seen around. Thanks.

http://bambusabicycletta.tumblr.com/


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## Deru (Jan 4, 2008)

Freddy Salgado said:


> Wow Deru, your bike tubes are beautiful. The shakuhachi flute is by far the most impresive item I have seen made by bamboo & testimony to the durability of bamboo material.
> Winter here in NZ so will have my fire pumping for next few months, will toss in some bamboo tubes in chiminy to have a go at carbonizing some bamboo. The sights you pasted are best I have come across so far.
> We have our fair share of earthquakes in New Zealand but nothing like what happened in Japan, wish you all the best and speedy recovery thanks for taking time to chime in Deru. If anyone wants to pool info on bamboo bikes we started a fb page called bamboo bike riders, its general independent info on natural fiber bikes.


I love the shakuhachi's sound and some others japanese musical instruments like sanshin.

I talked with a bamboo supplier and he explain for me how the bamboo is treated. 
The steps:
1 Haverst the poles in january until march. (winter)
2 Chemical treatment in autoclave(special bio-based substance) or boiling the poles with the substance.
3 The curved poles are straightened by fire.
4 The poles are dyed with a water based and natural dye.

The main problem in Japan after the earthquakes and tsunami is the Fukushima's atomic reator. 

PS: Sorry about my English, I'm not so good in English.


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## posey24 (May 31, 2011)

thats freakin awsome. Would it be possible to make one for downhill?


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## discombobulated_conundrum (Aug 2, 2008)

Unsure if this was asked before but do you hollow out the poles or just leave that thing inside the nodes when prepping the bamboo poles?


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## 96firephoenix (Mar 26, 2010)

your blog mentions that you only weigh 170... how do you think it would hold up to 210? I'm really curious about the whole bamboo frame, simply because I've heard how bamboo is one of the strongest natural materials, but for some reason, I'd be really afraid to sit on one for fear of A) breaking the bike and B) getting bamboo splinters in my butt.


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## 1997bontragerb1 (Jun 8, 2011)

*jump*

you probley shoudnt jump that bad boy it might break at the weld points


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## Drew Diller (Jan 4, 2010)

Want me to take some videos of me going off some jumps with my rigid-front bamboo mountain bike?

Went off a two foot drop yesterday. Two endo crashes in the last month. Four other crashes in the same time period.

It's tough stuff if you use proper species and pole diameter. The "weld" points are made of carbon or some other fiber, and if you use enough, is suitably strong as well.

How about this?


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## Drew Diller (Jan 4, 2010)

discombobulated_conundrum said:


> Unsure if this was asked before but do you hollow out the poles or just leave that thing inside the nodes when prepping the bamboo poles?


If doing heat treating instead of long-term natural drying, yeah, poke out small holes in the nodes so that heat distribution is even. The expanding air also runs the risk of cracking the wall somewhere because of the sudden pressure increase.


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## bboyuseless (Feb 21, 2011)

sorry for the delay
Posey24: This bike will be meant for downhill.

discombobulated_conundrum: nah, the membrane helps support the tubing so I just poke a small hole in the center of it so air can communicate through the chambers and leave the rest.

96firephoenix: we'll see! I'm using a 650lb spring for my rear suspension so I will design the bike to handle that and forces up to that.

Drew Diller: Yea please make some videos and post em here i'd love to see them!


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## Drew Diller (Jan 4, 2010)

Well they certainly don't compare to DH duty jumps, but I'll see what I can do when the trails dry up (rain in MN today).


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## bboyuseless (Feb 21, 2011)

new posts are available


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## Velosoxraptor (Jun 23, 2010)

Where is the best place to get the dropouts? I want disk brakes.


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## Drew Diller (Jan 4, 2010)

Velosoxraptor said:


> Where is the best place to get the dropouts? I want disk brakes.


http://www.paragonmachineworks.com/
http://www.cycle-frames.com/

Paragon in particular has some nice ugly (but they're titanium, so you don't have to dick around with insulating the aluminum from corrosion against carbon) dropouts on clearance: http://www.paragonmachineworks.com/cgi-bin/commerce.cgi?preadd=action&key=CL0014


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## kikodegallo (Jun 29, 2011)

*Bambu bike*

I just saw a post about a bambu bike and it looks pretty amazing.


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## bboyuseless (Feb 21, 2011)

Paragon helped me out with dimensions for my own dropouts which was incredibly nice, I would not have expected it. If you want high quality stuff for a little higher of a price, go there, It will ensure superior quality. Otherwise, Nova cycles sells some good stuff too. I get some of my tubing from there.

http://www.cycle-frames.com/bicycle-frame-tubing/


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## Drew Diller (Jan 4, 2010)

Per earlier offer to hit some jumps, I visited the only local jumps I know about... they are embarrassingly small. I'll have to broaden my horizons a bit.


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## bboyuseless (Feb 21, 2011)

Bambusa Bicycletta

For anyone who is still interested, and to bring this to the top, the bike is done, has been ridden and is awesome. The link to the blog is up along with a quick picture. 
Let me know what everyone thinks.


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## Drew Diller (Jan 4, 2010)

High five, man. Looks great! Makes me want to get my ass back in gear for the bamboo FS I have in mind.

High five.


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## bboyuseless (Feb 21, 2011)

For your viewing pleasure, more info on the blog!


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## Deru (Jan 4, 2008)

Wow amazing job!


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## 2fargon (Jan 22, 2011)

Completely badass! Would love to ride that thing. Headed to your blog


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## davesauvageau (Jan 8, 2010)

Great job man! Just curious, what is your headtube angle?


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## cdn-dave (Jan 6, 2007)

nice ride!


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## bboyuseless (Feb 21, 2011)

71 degrees.


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## asphalt_jesus (Aug 13, 2010)

*Questions*

How do all the details of the seat post/seat tube work out exactly? Are you finding a bamboo segment that is just right inside diameter? I saw that there was a milling attempt early in the bambusa bike for the seat tube and post. I may have missed how that finally worked out.

Is there a way to calculate/estimate the number of layers required to join the tubes? Just wrapping until it seems good enough seems kind of haphazard.

All very interesting and very well done.


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## bboyuseless (Feb 21, 2011)

For the seat tube, I had two options: milling an aluminum sleeve to glue into a bamboo tube and then fit the seat post clamp over both. In order to cut down on dissimilar materials being bonded together which could eventually result in de-lamination, I used a very large 1" reamer to ream out a bamboo tube to the size of the seat post. Not the best or easiest choice but it worked for what I needed it to do. It took two tries in order to ream all the way down to the first membrane without splitting the culm of bamboo. I would have liked to use a larger seat post (31.2 would be ideal) but a 1" reamer was all i had. 
Oh, and I also used a lathe in order to turn the reamer, set it to the slowest speed and reamed the bamboo tube by hand. It was difficult and took alot of wax for lubrication. In the end, the hole was for the most part, perfectly circle. The seat post fits in the tube and clamps to whatever position I would like (no slipping which I got lucky on). 

For the layers, there are formulas you can use in order to calculate layer numbers in certain positions when building composite bicycles but theyre all calibrated for carbon fiber and I also don't know any of them. 
Since I'm using abaca fiber, I made educated guesses based on my knowledge of bicycle construction. Where the most stressed points are and how the stress will be delivered. The beefiest parts are the bottom bracket which has about 4-5 layers and a large surface area for coverage (very very important) and the underbelly right where the downtube connects to the headtube. The whole bottom area of the top, frontmost lug. There are about 6 layers there. I did it this way due to stress dangers. If the bottom bracket breaks, it will essentially fall out from underneath me and hopefully my ass will hit the seat. If the headtube lug breaks, the entire bike splits in two, my face hits the handle bars and I hit the ground like a sack of potatoes. Clearly more dangerous. So simply out of caution, I went extra-extra beefy on the top tube lug. 
In retrospect, I would'nt have done any harm in adding an extra layer to the Bottom bracket. It would have made the drive train stiffer. Oh well, next time...


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## donk (Jan 28, 2004)

*Miters*

Anyone have comments on the benefit/necessity of mitering the tubes if you are using the styrofoam lug method of construction?


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## Drew Diller (Jan 4, 2010)

donk, I can.

I've built four frames, using two different bamboo species and either mitering or a filed-down lug core material.

Mitering gets you out of the jig faster so you can apply carbon in an open area - you don't have to be careful with a fragile core material. It's also a pain in the butt because bamboo isn't perfectly round.

I haven't noticed a difference in stiffness due to mitering - I have one mitered frame that's decently stiff because I did a good job on the carbon, and another mitered frame that isn't stiff because I did a poor job on the carbon. Further, I have a frame with lug cores that is stiff because I did a good job on the carbon.

The next combination I'm going to try is a lug core with a ply or two of carbon, and let that set so I can get out of the jig quickly to do the rest of the plies with room to move around.


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## bboyuseless (Feb 21, 2011)

personally, I'm working on a tree-esque setup with aluminum tubes possibly branching out of the Bottom bracket which would slip into the bamboo then the mitered bamboo would fit right up against the contour of bottom bracket so there would be an internal brace and the outer wrapped layer of abaca fiber. This would only apply to the bottom bracket where there are torsional and centrifugal forces in multiple directions that are also cyclical which, even with bamboo, will fatigue and eventually rupture. It may add a little weight but how much can you really pay for strength and peace of mind?

This is all on the next bike that is


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## bboyuseless (Feb 21, 2011)

Here is the reamed tube and how the seat post fits right into it. The other tube was the split failure.


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## bboyuseless (Feb 21, 2011)

Here is the mitered tube. not the best way to set up a BB.

Also, has anyone else ever worked with Abaca fiber before with composite bikes? I did a little research and found that the internet said it was supposed to be the strongest natural fiber. Does anyone have any concrete information on it?


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## Drew Diller (Jan 4, 2010)

People who currently do or have in the past worked with natural fiber lugs, off the top of my head:

Calfee
Bamboo Bike Studio

The former uses _Phyllostachys *****_ with hemp lugs. The latter use _Dendrocalamus strictus_ and carbon lugs but I believe they experimented with natural fiber lugs in the past.


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## asphalt_jesus (Aug 13, 2010)

Would it be better/easier if you stuck a Titanium sleeve in the seat tube? I picture steaming the seat post end of the bamboo and then gluing the sleeve in place. Push come to shove, drill through and pin the bottom of the sleeve/bamboo seat tube. 

My limited experience with milling really hard woods give me a little insight into how hard it was to do that work to the bamboo seat tube. I don't want to do that.

I'm assuming Titanium to be the only choice for the seat sleeve because there is no corrosion issue between the bamboo and Ti sleeve. I would think there would be corrosion/bonding issues with an aluminum or steel sleeve. On second thought, maybe a preformed carbon sleeve would do the trick. I don't know too much, so I could be setting myself up for some unhappy surprises.


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## bboyuseless (Feb 21, 2011)

I'm not sure if there is galvanic corrosion between wood and aluminum honestly, that would be something to find out, or if there is galvanic corrosion between wood and titanium but I do know that expansion and contraction of materials when subjected to gradually increasing and declining temperatures (much like the ones we have between seasons in New England) will lead to de-lamination between the materials. Aluminum has less expansion and contraction and has a slower, more uniform rate. Bamboo expands and contracts quite a bit and very un-uniformly. Clear coating will help prevent this (as will drying, curing, smoking, heat treating or any other method of removing water from wood) but the best way to avoid de-lamination is to simply find other ways of making things than bonding two different materials together with glue. So, thats where the idea came from. 

I mean, it's all in technique, reaming out the tube was very difficult and had an immense amount of finesse involved but I believe that if I did it once, I can probably do it again and if it yields a safer and better product then I'm willing to do that. I'm definitely going to invest in a metric 31.2mm reamer or 31 or 32, not sure yet. In order for me to do it again on the next bike and use a larger seat tube.


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## bboyuseless (Feb 21, 2011)

and de-lamination occurs over a while (a year or less) and is more common in materials far different from each other, like metals and woods. Hence why I chose abaca fiber, being an organic fiber It will have a more similar rate to wood. Plus I think It looks way nicer than carbon in my opinion, less harsh contrast between bamboo and lug, very subtle and sleek.

Thanks Drew, I didn't know the specific species each of those companies worked with, very interesting.


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## asphalt_jesus (Aug 13, 2010)

bboyuseless said:


> ... Bamboo expands and contracts quite a bit and very un-uniformly. Clear coating will help prevent this (as will drying, curing, smoking, heat treating or any other method of removing water from wood) but the best way to avoid de-lamination is to simply find other ways of making things than bonding two different materials together with glue. So, thats where the idea came from.


This is an important point for those considering a bamboo project. I was tempted to do a simple build by replacing most of the main tubes in a unspecial frame set using the joint stubs (+/- 3cm) to do the alignment/bond setup for me. But the expanding/contracting against a joint stub has a probability of delamination. How much? Too much for me.

If the bamboo tube fit the head, seat, and down tube stubs loosely, and wrapped per the photos then I think you eliminate the risk of a press-fit delamination due to environmental factors..

Do the resins have a moisture permeability rating?


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## Drew Diller (Jan 4, 2010)

Interesting thoughts on delamination. I know they shrink with heat. I tested some D strictus the other day and a 19" rod lost 1.5mm of length after an hour at 350 F. I didn't think to check the diameter. I'll have to do some more testing with strictus and P *****.

So far I like the strictus better. It can survive a serious pounding with a hammer, seems pretty crash tolerant.

FWIW, Boo Bicycles and Bamboo Bike Studio have suffered zero delamination problems (Boo also uses strictus).


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## bboyuseless (Feb 21, 2011)

Yea, there probably are better species for avoiding de-lamination and impact breakages. When bamboo is initially heat treated and the water is driven out of the wood, it shrinks immensely. Very noticeable amounts. Bamboo being an organism, I'm sure some species do this more than others. If someone wrote a book on the best species for bike building and why with a review of a good number of bamboo species, that would be an excellent reference to look at for those looking into the art of making a wooden bicycle. Anyone know if that exists?


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## Drew Diller (Jan 4, 2010)

Well, there being arguably a handful of professional quality bamboo frame builders, and some of them are reasonably protective of their tacit findings, information on this is pretty sparse. We have to write the book, and not all of us know what we're doing yet (meaning, me).


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## asphalt_jesus (Aug 13, 2010)

Drew Diller said:


> Interesting thoughts on delamination. I know they shrink with heat. I tested some D strictus the other day and a 19" rod lost 1.5mm of length after an hour at 350 F. I didn't think to check the diameter. I'll have to do some more testing with strictus and P *****.
> 
> So far I like the strictus better. It can survive a serious pounding with a hammer, seems pretty crash tolerant.


If you heat treat some more bamboo, can you post inside diameter changes?

I think I may be overstating the risks a few posts ago. I was picturing some milling on the inside of the bamboo for a tight fit against an alloy frame stub. I think if it's a close fit with no milling, maybe a fiberglass wrap between the two materials would make it tight enough and eliminate potential corrosion issues and give it room to move.

The other test I'd like to see some measurements on is simulating 100 F heat and near 100% humidity for a few hours from a reasonably low-humidity known state. While I'm asking for skittles and a unicorn, put it on a test jig and test for CEN criteria in that sauna.



Drew Diller said:


> FWIW, Boo Bicycles and Bamboo Bike Studio have suffered zero delamination problems (Boo also uses strictus).


That you know of. I'm definitely not making any claims about their product. Or, maybe you work there?

Great topic. Nice work all around.


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## Drew Diller (Jan 4, 2010)

asphalt_jesus said:


> If you heat treat some more bamboo, can you post inside diameter changes?


Sure thing. Need to build a destructive jig too.



asphalt_jesus said:


> That you know of. I'm definitely not making any claims about their product. Or, maybe you work there?


I don't work for either of them. I made a bike at a BBS session, and I simply asked and got an answer in both cases. I'm simply taking them at their word.


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## Fahzure (Jul 26, 2011)

How does the bamboo dually ride?


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## bboyuseless (Feb 21, 2011)

dually? The bike rides great! there is a little flex in the drivetrain but the rear shock works fantastic with the bamboo.


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## shimanogears (Mar 23, 2012)

Zachariah said:


> Nice! Can Bamboo be painted, or is it best to leave it natural?


of course bamboo can be painted but the 'bamboo' will be gone if you paint that.:thumbsup:


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## bee (Apr 7, 2008)

How much different is building carbon frames? Are the glueing of the joints the same?


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## bboyuseless (Feb 21, 2011)

If you are building a lugged carbon frame, no the process is the same.


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## mickmutante (Apr 22, 2012)

Nice post... and excellent work.!


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## cdn-dave (Jan 6, 2007)

Any advice/pictures out there on the rear dropout junction? I've epoxied my CS / SS over the remaining stubs (~5cm) of a cut-out dropout, but how should the hemp wrapping over top be applied?

I'm concerned with getting a good enough bond - the epoxy on the inside is more or less a placeholder for the bamboo. That leaves just a couple cm of dropout to bond the outside of the bamboo CS to. Wrapping simply around the circumference of the bamboo won't bring much, so how can I best make this joint??

Thanks!


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## cbchess (Dec 20, 2003)

The dropouts I used were from a surly cross check steel frame. If you look at this picture you can see the bamboo support I added.

Closer to the drop out you can see the steel support that was part of the original drop outs. I wrapped this in carbon fiber and back toward the seat tube in order the "tie" the drop out to the seat stay.

Rear disc brake by cbchess, on Flickr

The inside of the drop out ends were empty steel tubes maybe 1 to 2" long (the original seat stay and chain stay ends). These I filled with an epoxy and filler mix like saw dust and milled cotton fibers. After that dried I had really roughed up the ends of the old stays with some very rough grit sand paper - like 60 grit. Then, before I pushed the dropouts into the ends of the bamboo stays, I filled the ends of the bamboo stays with the epoxy and filler mix.
Then I wrapped the steel drout out bits in a carbon fiber layer which went into the bamboo stays ends. This ensured a nice snug fit

After that setup and dried. I wrapped the whole dropout and seat stay/ chain stay joint at least 3 separate times with a carbon layup then compression tape and a full cure.

This picture you can see the orignial drop out peeking out of the jig blocks. That little blue cross piece bit is the part I wrapped in carbon fiber and back towards the stays.
You can see the filler mix ozing out of the ends of the bamboo here. 
rear dropout close up by cbchess, on Flickr


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## cdn-dave (Jan 6, 2007)

Cool! Thanks for the explanation cbchess and cool flickr pics too!

I guess I'll go ahead and file away the inside of the stays down to the steel stubs, so that I can reinforce it better from the inside out.


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## Freddy Salgado (Jun 4, 2009)

Sick rig dude!

In regards to a better species for avoiding de-lamination I think it has more to do with material you glue it to than the bamboo type you use. From what I read on Calfee's web sight they had problems with carbon material used for lugs because of thermal dynamic expansion difference between materials, and no longer offer carbon option for good reason, no one has more bamboo bikes in the field or as long than Calfee.

I don't use the same species of bamboo as Calfee or Boo. For sure there are some species of bamboo you want to avoid but for the most part it's harvesting at right time, age of the bamboo and the way you treat, (dry) bamboo that will yield a strong bike. I made a bmx bike, had it back flipped out of a bowl to flat ground a few times and it held up fine.

A book is not a bad idea for the diy type just to keep someone from serious injury also to insure strong bikes are made so they have a chance to be represented in the right light.



bboyuseless said:


> Yea, there probably are better species for avoiding de-lamination and impact breakages. When bamboo is initially heat treated and the water is driven out of the wood, it shrinks immensely. Very noticeable amounts. Bamboo being an organism, I'm sure some species do this more than others. If someone wrote a book on the best species for bike building and why with a review of a good number of bamboo species, that would be an excellent reference to look at for those looking into the art of making a wooden bicycle. Anyone know if that exists?


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## durianrider (Mar 16, 2009)

My web works is holding up pretty good after a year of thrashing. In another 5 years time we will see bamboo technology even more advanced for sure I agree.


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## mickmutante (Apr 22, 2012)

I built this bike, my first prototype, and I used local bamboo, and CF cloth. I think I put 1600km on the trail, and road, with a lot of mud, rocks, rain... some crashes (funny crashes). And for now everything on the bike is ok. No de-lamination, or failure on the material.


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## Drew Diller (Jan 4, 2010)

mickmutante said:


> I built this bike, my first prototype, and I used local bamboo, and CF cloth. I think I put 1600km on the trail, and road, with a lot of mud, rocks, rain... some crashes (funny crashes). And for now everything on the bike is ok. No de-lamination, or failure on the material.


Nice work. Could you share what species of bamboo?


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## cameronbrown (May 21, 2012)

durianrider said:


> My web works is holding up pretty good after a year of thrashing. In another 5 years time we will see bamboo technology even more advanced for sure I agree.


Beautiful

How did you get the deep dark colour? Stain?


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## Drew Diller (Jan 4, 2010)

cameronbrown said:


> Beautiful
> 
> How did you get the deep dark colour? Stain?


You can heat cure bamboo to change its color some. Also, there is a particular species that literally becomes black with age.


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## mickmutante (Apr 22, 2012)

Drew Diller said:


> Nice work. Could you share what species of bamboo?


I do not know the specie, they call it "green bamboo". And I chose 5mm wall thick rods.


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## cameronbrown (May 21, 2012)

I just finished a bamboo bike build myself. Feel free to check out the blog posts about how I went about it. It was my first foray in to any sort of frame building, and I learned quite a bit along the way.

How to Build a Bamboo Bike - Part 1 - Planning Things, Measuring Stuff & Getting Jiggy With It | Cameron Brown


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## sheepdogreno (Dec 21, 2012)

i can now mark off that i have seen a bamboo bike! This is quite cool!


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## bikeofbambu (Jun 16, 2020)

I just bought a bamboo bike and it's beautiful, although I don't know if as much as yours, I would like to get your opinions


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