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Bamboo Bike A Reality
markjugg writes "The American Bamboo Society has a page describing a working bamboo bike. This is a strong step towards making bicycling more sustainable, expecially in contrast to aluminum, one of the most resource demanding materials that exist."
Since it's only got one gear, would it be possible to control speed with the chain?
There are no trails. There are no trees out here.
expecially in contrast to aluminum, one of the most resource demanding materials that exist.
That's funny. Aluminum is indeed expensive to extract and process and that's why it's also the most recycled mineral(?) in existence.
Bicycling more "sustainable"? Haven't the environmentalists been trying to get us all to change to bicycles from cars supposedly because of the pollution that cars generate? And now not even bicycles are "sustainable" because they are "resource intensive"?
When does it end? Should I just stop using resources altogether (i.e. die?)
I won't post this anonymously precisely because I mean this quite seriously and not as a troll. Mod me down if you must.
Justin
Before you say that bamboo is weak and easily dismembered [snip] What makes it possible to build bicycles from it is that it is stronger than steel when strained in the longitudinal direction, 17% to be exact.
Yes, but steel/aluminum won't rot, won't get eaten by bugs, are stronger in NON-logitudinal directions(ie, twisting- think about when you pump the pedals holding the handlebars, yes, you're twisting pieces of the frame!)...and when they fail, they (usually) just bend. Bamboo cracks, and then it just disintegrates.
Please help metamoderate.
I wonder if this would me more or less expensive than a traditional bicycle? I usually try not to pay more than $200 (CDN) for a bike, because they always get stolen (even if they're locked up... those bastards).
:)
Since bamboo is so plentiful, I hope this would be uber-cheap. It would be great if I could ride around on a $15 bicycle... I wouldn't really care if it got stolen, but then again, nobody would really want to steal it if they knew how cheap it was...
Parent: yeah, right. Imagine this - you're going at full speed. Downhill. You'd better keep your feet as far away from the pedals as possible - if you don't want to break your legs.
Hell is not other people; it is yourself. - Ludwig Wittgenstein
The thing is, unlike trees bamboo reaches usable size in three years, and no need to replant after harvesting. Rather than deforest you can simply plant your own. And if they deforest correctly there is a new forest within three years. In the process of producing carbon fibre don't doubt there is a crazy amount of pollution and environmental destruction. Just think of the chemicals in the resin, and the use of sulphuric acid and petrochemicals in the fibre production process. All in all, the point is that I couldn't grow carbon fibre in my back yard no matter where I lived on this earth. Did it ever occur to you that in underprivilidged societies a bamboo bike may be a whole lot cheaper than carbon fibre?
many die hard mountain bikers use single speeds, especially for training. These are DIRECTLY tied to the wheel, no coasting action what so ever. (although they DO have normal handbrakes brakes, running without is just plain stupid, you use those for quick emergency stops only)
I question whether this is an environmental good thing. Using bamboo in stuff means *importing* bamboo - because if you try growing it anywhere other than where it's supposed to be, you can destroy your own local ecology. So it has to be imported, and you're economically tied to the few countries that can grow it in quantity and to the right quality. Steel and aluminum, on the other hand, are easy to get locally, and can be shaped in ways bamboo cannot. Plastics and carbon fiber can also be made locally, and carbon nanostuff will eventually also be available locally. And all of these other materials can be recycled, whereas bamboo can only be burned or mulched.
You also can't mass produce bamboo products - as it says towards the bottom of the article, the guy that makes these needs to hand-select everything for quality. Remember, you can cut the length of these, but not the diameter - you're stuck with whatever diameter it grew to - so precision is extremely difficult.
Sure it is funny, but the bamboo society is missing a fundenmental point...
I disagree with this non-environmental friendly stuff regarding Aluminum and Steel. These two metals are some of most recycled materials that there are. What do you think happens to old ships, cars, buildings? They are not buried, but smelted again.
In fact this is the beauty of these metals. They can be essentially recycled 100% unlike plastics and papers that always need additives. The reason we do not know about this is because steel and aluminum have been recycled for decades...
"You can't make a race horse of a pig"
"No," said Samuel, "but you can make very fast pig"
Well I think the solution is clear. Laminate the bamboo with carbon fiber:)
I'm not an engineer, but the kind of force applied when you push down on one pedal and pull on the corresponding handlebar seems like you'd be attempting to twist and bend the bamboo poles. The bamboo is only stronger than steel when you're pushing on each end.
You'd eventually wear out your bike like that. Much faster than any commonly used bike material, I'm sure.
I'd be concerned about the glue being too brittle to deal with serious vibrations, too, but they might be able to come up with the right kind, I'm sure.
There are no trails. There are no trees out here.
Fine, get excited about the technology involved here, but spare me the statements like that. Everytime I ride to work, I keep a car or about 1/30th of a bus off the road. (I realize I'm not actually 'keeping the bus off the road', but work with me here.) I don't even need to go on about what a retarded statement that is, to call bicycles anything but a vehicle of sustainability.
What's next? Smack-talking a water powered car because it's a drought season?
You know what?
Sure, but what's required in order to refine raw aluminum (or what ever you call the ore)? Lots and lots of electricity. How's that electricity produced? Power plants that: burn coal/natural gas (leading to air pollution), use nuclear fision (all sorts of nasty biproducts that we still haven't figured out what to do with, other than bury them), or hydroelectric dams (don't even get me started here).
Recycling aluminum & steel reduces the problem, but even that requires large amounts of energy (see above).
I don't think it's that big of a deal when it comes to bikes. The only bikes made from aluminum are the mid to high end bikes in the $500-$1500 range. The amount of aluminum used in these bikes is less than 6 pounds, typically. Most of the bike's weight is due to the gearing system, tires, strut system, crank and chain. These guys seem to be focusing on the low-end, buy your bike at Kmart crowd.
If you look closely at the design of an aluminum bike, you can tell not many resources are used as they use the least for weight purposes. I know the frame on my Cannondale is a couple of millimeters thick. The rigidness comes from thin walls on a fat tube.
Aluminum bikes aren't going to be around for much longer anyway, the price range for a good aluminum bike gets you right up there with titanium and magnesium alloy frames, which are superior in my opinion. Most of the trim parts consist of carbon fiber (wheels and forks on the better bikes use this).
I am not sure what the point in this article is. There are far greater wastes of resources in new car design as well as the actual bottling process of cans. If the media, or anyone else cared enough to be earth friendly, we'd do it in ways that were actually beneficial. Not by purchasing organic bikes.
A note on steel bikes. They aren't taking into consideration the actual alloys used when doing the comparison. No bikes are made with 100% steel. They use various alloies in the process.
I'm picky on this subject after commuting soley by bike for a few years. I would not trust my riding on busy city streets to an organic material, I'd much prefer the comfort of knowing the materials are consistent due to the manufacture process involved with metals. I highly doubt the bamboo is nearly as consistent if measured across the bike's whole frame.
Why worry about the glue? All "stick and cloth" aircraft such as the SPAD, Foker, Sopwith, Stearman, etc had spruce wing spars and ribs that were built with animal glue. The glue is stronger than the wood it connects. I wonder what holds all those carbon fibers together in the modern composite bike. Could it be a glue like epoxy?
...Well, from the picture, they are not using bamboo-to-bamboo interfaces at the high-stress areas (head tube-top/down tubes or bottom bracket shell), but are using metal lugs, much like many of the newer carbon-fiber racing bikes are again, so one does not have to make difficult carbon fiber-based lugs (like Trek's carbon bikes have). The results are not quite as pretty as a Trek, but if it's lighter and works, this usually trumps everything for most bike riders...
So the metal lugs take care of the complicated stresses at these points and only transmit compression/tension stresses to the bamboo tubes, and minimize torsion stresses along a given tube (probably by using "oversize" bamboo tubes also).
Another advantage to this is, if you crack a top tube in a crash, I would think it is relatively cheap to get a new tube put back in, instead of having to throw away the entire bike (i.e., Trek 5000-series) frame.
I know I would probably NOT trust a bamboo handlebar (besides, how would they ever grow a bamboo drop handlebar?), but other than that...
Yes, I realize that this article is about bikes for third-world countries, but if some sort of mandate from UCI came about to use more sustainable materials (if they can do it with bike frame shapes, they could do it with construction techniques and materials as well...) in exchange from deviation from standard "double-diamond" designs, then this affects a rabid, money-spending group of bike consumers...
While I appreciate some of the tech in the bikes that pro bike racers use, I know that for 99% of bike racers, it does not make the difference between winning or losing a bike race, finishing that century, or grabbing a latte across town.
It is a bit like buying a ferarri to buy groceries and run errands.
Those who have the $$$ (or think or want to project that they do) will always spend it. The rest of us who don't have to look for value.
It would be cool to buy a Colnago C-40 "ferarri" bike. But it's definitely not worth $7,000. Besides, the people who win bike races simply have better motors than those who don't. Their equipment doesn't matter much, if at all, compared to their peers. If everyone only had Schwinn Varsity's, the people who win bike races now would still be winning the races...
...the kinds of steel and aluminum alloys used in most high-end EuroAmerican bikes (i.e., not purchased at Wal-Mart, Target, K-Mart) is not the same rolled cold-steel tubes that the cheapest bikes use.
The bikes that the bamboo bike is hoped to eventually replace weigh about 40-50 lbs unloaded. They are BEASTS.
Remember, in Asia, they build skyscrapers using bamboo scaffolding.
The article mentions "longitudinal" loads (compression/tension), rather than torsional or bending loads.
As far as the rear triangle on your bike, that is specific to your bike. A bamboo bike could use a unistay (i.e., single piece goes from seat tube to a metal crown, where the seatstays then go to the rear dropouts), where the brake is clamped to the crown, and be just as "efficient" as your bike.
For 90% of the bikes sold and used in the world, they're NOT used for barrelling down single-track or alpine descents. They are used on flat streets at not much above walking pace. Braking efficieny is not a concern (as long as the brakes can lock the wheels with reasonable force, they're good enough).
On a tangent, in Thailand you can buy snacks of steamed rice with various goodies, cooked inside a section of bamboo. Buy them outside Hualampung Station before going on long train trips.
No, because a bamboo bike would be more expensive and less durable than a steel one.
The ability to have a cheap bicycle, made from sustainable materials is an incredible thing for these people
Except that it's impossible. Can they make a bamboo hub or chain? What about the lugs? Wheels? Gear wheel? Ball bearings?
I'm sure in Laos you can buy cheap Chinese-made bikes. (Flying Pigeon, eg). They ARE ALREADY "sustainable". All they need are new tires every ear or so, and put some oil on the chain when it rains, regrease the bearings once a year or two, repaint every 10 years. You find little roadside shops where guys fix bikes (patch flats, fix most other problems with a hammer and a wrench) for pennies in the third world. (I've biked in Indonesia, Thailand and China.) With minimum maintenance they last for decades. Bamboo bikes are a novelty item for rich Westerners, completely useless to the third world.
Excellent Points. One problem that needs to be pointed out is that the type of efficiency given for photosynthesis are not the same type of efficiency numbers given for solar panels. One would assume that both of these are the quantum efficiencies of the systems when in fact the quantum efficiency of photosynthesis is between 6 and 9%. The lower 0.2 percent figure may take into account the following issues (taken from lecture by Dr. Tad W. Patzek) 1. C3 crops are at maximum photosynthesis rate at 1/5 of full sunlight, so 4/5 must be dissipated as heat (experiments in laboratories are performed at low light intensity) 2. Crops do not cover the entire field area. 3. Upper leafs form an unbroken canopy, which blocks sunlight from lower ones. 4. In areas far from the equator, the ambient temperature is too low for appreciable photosynthesis. E11, Prof. Tad W. Patzek 3 5. At temperatures higher than 30 degrees C, photorespiration losses are high. 6. Water shortage and deficiencies in trace elements limit plant growth. 7. CO2 at 360 ppm is frequently a limiting factor. C3 plants can double or triple photosynthesis rate in augmented CO2 . After these factors are taken into account the yield efficiency is approximately 0.5 percent. The post specifies 0.2 percent. I have not seen a number this low in the literature. Also 20 * 0.2% is 4% not 10%. Did the post intend to use 0.5% for efficiency of photosynthesis? ( 20 * 0.5% = 10%). "authors undermine their case by making inaccurate claims" Some of these factors also apply to solar panels. Which reduces the efficiency to an extent.