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Bicycling Science, Third Edition
Released this April, David Gordon Wilson's updated Bicycling Science fills the gap between, on the one hand, shop manuals and training guides, and on the other the contemporary literature on human powered vehicles. Wilson, Professor Emeritus at MIT, navigates physics and physiology to produce a hefty source of insight.
Wilson splits his book into three broad sections -- the biology of human power generation, the physics of turning complicated muscle motions into linear velocity, and radical redesigns of the standard diamond bicycle frame.
The first section explains, among other things, the role of oxygen uptake and distribution, and gives empirical and theoretical backing to some, but not all, of the conventional wisdom surrounding cycling. The curious will find a detailed explanation of why high pedal cadence allows for long-term, low-intensity, high-efficiency power generation. Modifications to the standard choices -- from elliptical chain-wheels to hand-powered cranks -- are analyzed critically.
The second section might be jokingly termed "extreme high school physics." Wilson explains how people intuitively balance and steer on two wheels, and the design of braking systems to avoid flip-over. He gets down-and-dirty in the metallurgical literature to explain the role of metal fatigue in frame failure, and into fluid dynamics to discuss air drag in laminar and turbulent air flows.
Wilson manages to give a sense of how the different demands physics makes on all aspects of bike design cohere into the more-or-less efficient system that we recognize today as the road and mountain bike. Wilson is an innovator, but he has a healthy respect for current designs along with a good deal of skepticism for passing fads such as that for ultralight components.
The final section covers Wilson's love: the radical redesigns of human powered vehicles to enable people to not only cover vast distances or reach high speeds, but also to swim, submarine, fly and even hover or flap on the power -- between 100 and 700 W -- the "NASA standard" man or woman can provide on timescales between hours and seconds.
The text occasionally jumps into a wider historical and social context to provide lighter relief, such as the diagrams that compare cycling's efficiency to other modes of of transportation (cyclists handily undercut a fully loaded diesel commuter train for calories expended per rider.) Wilson is not amused by those who would compare cyclists to dolphins or hawks in terms of efficiency, distance, or speed -- too bad. A brief rant against cars near the end is the exception to the rule of Wilson's professional, honest style.
Bicycling Science can be used as a handbook for the armchair designer of human powered vehicles. Or, if you prefer, as a way to answer the nagging science questions that arise after a thoughtful bike ride. Perhaps its most inspiring use, however, is as a bed-table compendium of stand-alone investigations into what engineers have come up with on a device that has been perfected, again and again, for decades longer than the internal combustion engine.
You can purchase the Bicycling Science, Third Edition from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, carefully read the book review guidelines, then visit the submission page.
No way, gotta ride a recumbent; Espically when gas is $3.00 a gallon!!! :(
This is my signature.
But the bicycle from a broad design perspective has not changed much since its invention, save from a departure from amusingly large front (or is it back) wheels. So it seems to me that the bicycle is far from optimised in terms of muscle use. I've seen various contraptions over the years that I suppose attempt to imrove on this. One that I saw just a few days ago appeared to be powered like a rowing machine. Another more popular variation on the cycle has the rider sit much lower to the ground. But I believe this one only serves to have the rider in a more upright position. So does this book point out the "best" design for the cycle?
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
You'll fit in real good at the scientist loony bin in the "She Blinded me with Science" music video. If it looks out of place there (like a regular bike would), it is not "real geek".
Don't blame Durga. I voted for Centauri.
Cycling science has really come on in the past few years. I remember the bicycles of my youth resembling drainpipes welded together - heavy and clunky with all the response and verve of a coffee table.
Now I was somewhat suprised to find that more modern bikes are superb machines. Cheap. Reliable. Light and really really fun to ride.
The added benefit of being a) ecologically sustainable and b) acutually *quicker* in the city is just a bonus.....
This one goes out to all those car luvin' geeks. Borrow a high quality bike and see what the rest of us are a raving about.....Do this now.
Remember kids! Guns don't kill people - Americans kill people.
I'm working on modding my mountain bike, the same way people mod their PC cases... with come cool lighting from fossilfool.com and some strategically placed EL wire.
I'd love to put a laptop somewhere on it, but I have yet to figure out what it should be used for, and I dont want to put wi-fi on it.
I am a certified geek, and I love my bikes (I have about 6) For me tinkering on a bike is more fun that tinking on a computer. Bikes are very simple machines, but they require a lot of work to run perfectly. Bike are also high tech. Forget the old schewin cruiser you rode as a kid. todays bikes are made out of things like titanium and carbon fiber. The cycling industry actually perfected the manafacturing of carbon fiber. Car makers are begining to adobt it, the new sony ultalight laptop uses it, and there are rumors of apple using it in their new powerbooks. I'd love to have my laptop math my bike. Bicycles are the most efficent form of traspertation out there. As a geek, you should admire that. My only problem with bikes is that the nearest Fry's isn't close enough to ride to.
sorry 'bout the mess...
I have recently and at long last become reacquainted with my bikeE recumbent. Or, well, semi-recumbent as some people like to call them, since it's more like a propped-against-a-wall position. However, I guess a *true* recumbent would involve you lying senseless on a mattress or something, so I call kibosh on that aspect of the name game ;)
...) low-end: a bit heavy, a lot cheap (compared to many recumbents, which are designed and priced like sculpture). I had hoped they represented a sufficient mainstreaming of recumbent bikes, and a sufficient lowering of the price, that they would fill an obvious market gap and thrive, but ... No. Turns out they were not able to pull an eMachines, despite the similar naming scheme.
:) For Steve Roberts with his 210 gears, maybe, but not for me with my mere 21 ;) It's also more for streets and other flattish surfaces than for mountainous territory ;) However, the tires are sufficiently knobby it's certainly not confined to artificially perfect racing conditions. For the places and reasons I'm likely to ride it (mostly urban transport, for fun and utility, grabbing milk from the store etc) it's perfect.
As recumbents go, bikeE bikes are (or were, since the company is now out of business, but *are* in that their products still exist
So, now after a year of not riding it (long story, friend's delivery plan from the other coast was interrupted), I have the pieces, and soon will re-assemble my heavy but super-cruisy blue semi-recumbent.
Riding recumbent takes a few minutes to adjust, less so probably on the bikeE than on the truly radical ones, which I have long wanted to try but never have. It's cruisy! turns are a bit slow (long wheelbase), hills are enough to make me walk a lot of them, in contradiction to claims that they're no worse on a recumbent than on a conventional upright bike. Uh, Yeah right
(Who is Steve Roberts, you ask?)
However (and this is the reason I have bothered to type this much on an old bike), I have not yet located a bike rack that would hold one of these on the *back* of my small station wagon (subaru legacy outback). Has anyone seen one of these? I don't want a rooftop rack for it -- unless someone can provide evidence that rear carriers are just as bad, fuel-wise. Around town, the fuel difference is not so bad. I just ended a 9,500 mile road trip though, and may be taking one of similar length in August. At current gas prices, and even at old ones we may ne'er see again, I don't want to add anything unnecessary to the fule bill.
timothy
jrnl: http://tinyurl.com/c2l8yr / foes: http://tinyurl.com/ckjno5
There is nothing that compares to a bicycle for efficiency of transport. I ride 60-100km most days and the only fuel I require is a protein shake (aprox. $1.00) and a couple of bottles of water. Positive physical side-effects aside, there is nothing more enjoyable than passing some Bicycling Science, Third Edition reading weenie on his tricked out, rarely ridden road bike! BTW, true geeks ride recumbants! (those ridiculous looking Lazy-Boy contraptions)
UCI (Union Cycliste Internationale, the international bicycle racing governing body) has a number of controversial (depending on who you ask) rules regarding bicycle weight and design.
Besides the 6.8kg weight minimum, there's the "double diamond" frame design restriction, that effectively bans all non-traditional frame designs from upper level racing. Trek, Softride, Kestrel, and a number of other companies have designed some very novel wind-cheating non-traditional frame designs--ostly revolving around eliminating the seatpost. Due to UCI regulations, you'll never see anyone ride one of these in a road race.
Triathalons (Ironman, etc) are regulated by a different body, so the rules are different there, with more emphasis on "aero" designs, time-trial bikes, mainly because drafting is disallowed. This is where you see some of the more interesting frame designs.
It doesn't require a laptop (too heavy anyway) but a PDA. I just bought a personal GPS receiver and am working on a program for my Pocket PC to give me audible directions while biking/driving using maps I build myself (tracing over aerial imagery).
Basically it comes down to technique. On most reasonable length, gradual (less than 4% grade) hills, you can find this happy zone where you really aren't pedaling any harder than on flat land. It took me about 3 or 4 months of solid riding (150+ mile weekends) to really find the timing and gearing. For me the easiest way to find it was to drop to my middle front ring with the smallest back ring and work down the gears from there. I am generally happy on long hills somewhere in the middle of the back rings and on my middle front ring, shifting up or down as my legs dictate.
bkr
"Growing old is inevitable; growing up is optional."
Yeah, as someone who's been serious about cycling (competitively) for the last 15 years, I have to agree with the other poster that "ultralight components" are not a passing fad. Cycling, perhaps more than any other sport has a materials science and mechanical engineering war brewing. Every company is looking for an edge in materials -- look at the recent adoption of scandium-aluminum alloys for frames. Old ideas get rehashed every so often -- it used to be that carbon fiber frames were three main tubes of carbon, lugged together with aluminum. That "fad" passed away, but has returned now that people realize that blending materials in certain parts of the frame have benefits -- adding carbon seatstays to an aluminum frame cuts weight and dampens road-shock before it reaches the rider...and recently, LeMond bikes have shown up where the primary stress-bearing portion of the frame (the chainstays, down tube, and head tube) are titanium and the remainder of the bike (seat stays, seat tube and top tube) are Trek's proprietary OCLV carbon (LeMond is owned by Trek)...making for a very light bike that rides smoothly (the carbon upper portion gives it nice shock absorption) and is torsionally stiff (thank you, titanium), so it rides nice, is much lighter than typical titanium frames, and it sprints and climbs like a m-therf-cker.
Sure there are fads, and they pass, but most of the time, Joe Average bike user isn't going to be concerned with it, becaus a Joe Average bike shop bike (not a department store bike) sees those development years after the "lightweight, passing-fad" parts have been put through the evolutionary wringer of the market. If the design concept works, it trickles down into Joe Average bikes -- things like aluminum frames, indexed shifting, threadless headsets, etc. -- and if it doesn't work or is too expensive to be anything but a high-end product, then you won't see it on entry-level bikes. Things like titanium bolt sets (expensive, not worth the weight savings) come to mind.
The last two to three years have brought some seriously interesting developments, some of which I suspect will be see in Joe Average bikes within 5 years -- the aforementioned carbon seatstays, scandium-aluminum alloy framesets, paired-spoke wheels, etc.
Just because the market is being used to filter out what works and what doesn't, doesn't mean that every attempt at a lightweight part is a passing fad.
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I find downhilling on my mountain bike to be one of the few times where I feel completely and utterly stress-free. When you're doing something like 64 Km/h down a rutted, obstacle-strewn single track, you can't possible even think passing thoughts on anything beyond where your tires are going to be in the next few seconds. I always feel like a million bucks when I get to the bottom of the hill ... at least until I realize I now get to climb all the way back up. :-)
This is Kwajalein (9Nx167E), where I currently live. Green one-speed Huffys rule here - flat terrain, and why spend more than $90 if the damned thing's gonna be a pile of rust powder inside of 8 months? The most popular mod is a 3-foot extension of the handlebar yoke so you can rest your forearms on the handlebars without bending over. Bike trailers are a must, for transporting large boxes home from the post office or schlepping SCUBA tanks to the beach. Adkins diet is a killer, because you need carbs to pedal a bike, go figure! And most important, there are many more bikes than the few government vehicles prowling around, so bikes rule the road - yeah!
The local store has brought in aluminum-frame bikes with 4-speed internal transmissions - they'll last about 2 years before the steel components go. I have one, sprayed a couple of coats of clear Krylon on it, and it's still going after a year and a half - did have to replace the chain. But at $300 apiece, the economics of the green Huffy still rule.
Some folks with time on their hands will scrounge parts from Bicycle Heaven (where all rusty bikes go) to build their primary tranporation - hey, what's a little rust, or a off-true wheel that shoves the seat up your butt, when all you need is a ride from the dorm to the chow hall?
We do have competitive cyclists on-island, and they get into the standard stuff - aerodynamics, lightweight materials and such. But we also have folks who compete in the annual triathalon (aptly called "The Rustman") with "Kwaj-condition" bikes.
All this to say it's been interesting living in a world where bikes really do rule...
If you look at the issues, I think you'll find that far from being "dangerous" the health benefits of cycling are huge, big enough to overwhelm any other worries, like the risks of collisions (which probably aren't as high as you think they are anyway). Do some web searches, you'll turn up things like this.