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You can build a new window altogether in JavaScript, apparently, with no HTTP requests taking place. I think this is what your quote refers to.

See the javascript at e.g. sheldon brown's bicycle gear calculator page, line 422 (function showit()) and forward.

It basically uses document.write to build the whole pop-up results window.

(Yes, I was surprised to learn that such a thing was possible.)

I had a similar bike maintenance issue and found a very helpful site which is like a trip back in time to the 90s. It doubles as a way to show youngsters how websites used to be before the modern interpretive dance web design movement.

Why not? Vary the density and even the shape of the construction to simulate a spherical gravitational force with the hole in place. The basics of the idea aren't exactly new. It's sort of like the "stepped" starting line on an elliptical race track.

If you ever change your mind about wheel building:

In the wheel book by Jobst Brandt, he gives good instructions in how to lace up a wheel. Once you've done it his way, you can lace a wheel in 15 minutes before tweaking in the stand (which is where all the work is).

Also, I have learned from old man Stedman in Wakefield RI (dunno if he's still alive, he was in his 90s 15 years ago, riding his single-speed).

You always hear about not having enough tension in the spokes from various sources. Most of these are overzealous.

Stedman taught me that too much tension will make the wheel unstable, and the reaction of most people while truing is to tighten the opposing spokes more and not letting off enough on the tight side, leading to a progressively unstable wheel. I've taken this advice and it works. A hand built wheel by me doesn't need truing for an entire season sometimes.

BTW, i read that Jobst had a bad crash and broke his femur last year and he really hasn't come back. :-(

Then there is Sheldon's page on wheelbuilding.

http://sheldonbrown.com/wheelbuild.html

Sheldon's page is a wealth of information. - sheldonbrown.com

--
BMO - WWSD? (What would Sheldon do?) (in Firefox, this is squigglylined as a misspelling. When i right clicked on it, it suggested wisdom as a replacement. Indeed, Firefox, indeed.)

I'd also question the assertion that the frame has no seams, unless it is cast or MIM or the like. If so, I can't figure how that would be an advantage over a traditional butted or welded Al frame.

I think they're talking about the tubes that the frame is made from. See under "seamless": http://sheldonbrown.com/gloss_sa-o.html

"Simple brakes" is also an hilarious callout, to describe what are likely off the shelf cable pulled calipers not significantly different in design from every bike in stock at Wal-Mart.

Well, yeah. That's the point. Cable-actuated brakes are reliable, and when they do break, they're much easier to fix in the field than hydraulic brakes. They don't have quite as much stopping power as hydraulics, but for a mostly flat ride, that won't be a problem.

Until some genius^H^H^H^H^H^Hhacker photographs a photograph.

Good point. And it dispels any reason to believe film cameras are safe from digital hacking as well.

Do all the photoshopping you want, print it, photograph it. There, you have evidence captured on film.
 

I hear you.

Get a decent freewheel, though - I've got one of these, myself, and they're great. Purring like a kitten, too, and guaranteed to make pedestrians' heads turn when you're approaching. :)

It won't help with people using MP3 players, but then, nothing will, short of perhaps carrying a bullwhip...

http://www.sheldonbrown.com/harris/nuvinci.html

Compare to the price of an unmotorized downhill racing bike using the same class of components (never mind the custom frame), and you'll see that it's not out of line. High-end bicycle parts are built not just for performance (as is your sports bike), but also to minimize weight; the premium that comes with that latter goal is significant. (Also, $13K is a bit more than the 850X ran... I think that's what they're charging for the 850R now? The German-made Speedhub and associated parts run in the area of $2K or so, so there's a substantial difference in component costs between the models; that Speedhub, however, has a design lifetime of 100km with little maintenance beyond oil changes, and they tend to last well beyond that lifetime; 10 years into production, not a single unit had failed yet.

There's value for that money -- the focus on high-end parts buys robustness -- including suitability for offroad use, which most ebikes lack -- amazing handling, longer range (over 100 miles between both internal and external batteries, with an energy cost for that 100 miles of less than $.30) and a 20lb weight advantage on most other fully suspended ebikes. Really worth it? The money would be doing me a lot of good had I put it to principal on my mortgage, sure, but I'm healthier, happier... and as I said, it's a shiny toy. I could have bought plenty of vehicles (including many cheaper electric bikes) if I just wanted to get from point A to point B, but I had a tax return and a performance bonus, and I put them to use supporting an American business making a top-grade product with first-world parts, and in hindsight have no complaints.

They're some of the brightest, most original small businesses going. Makes you understand how the Wright Brothers came out of that environment.

My wife is a devotee of Terry Precision Cycling. It was started by a woman who couldn't find a bike to fit her. She happened to be a mechanical engineer, and the light bulb came on over her head. My wife's bike came with a homemade desktop-published manual that is among the very best manuals I've ever seen for any product whatsoever. The first time my wife had a slightly tricky technical question about her bike she used the "email us" contact link on the site and was, dare I say, thrilled when she got a long, detailed, helpful reply from Georgena [sic] Terry.

Another great example of brilliant self-publishing is Barnett's Bicycle Manual.

Take a look at Sheldon Brown's bicycle website for another great example of the true nerd spirit at its best.

I think he got it from the following link at thats why it is in alphabetical order: http://www.sheldonbrown.com/gloss_bo-z.html#brake

Well...
Titanium has a lower Young's Modulus than steel. Aluminum is lower yet. But if you calculate the specific modulus of elasticity, they're all pretty amazingly close to one another.
Sheldon Brown talks about this a bit.
If you need rigidity, you increase the cross-section, since stiffness is a function of a high power of cross-section times modulus of elasticity. A very modest increase in diameter, with corresponding decrease in section thickness, gives you a ti structure with the same weight and stiffness as a steel one. The interesting thing about ti is that it has about the same yield strength as steel, despite being only half as dense, so there are some advantages to using it.

Interesting link here:

http://www.sheldonbrown.com/brakturn.html

In fairness, the one time I went over the handlebars involved a collision with a fixed object, although I did on a seperate occasion have a nasty sideways skid from a sudden stop necessitated by a car door opening.

I have a faint memory of going over from my childhood but of course can't remember the full details ;-)

Of course on most bicycles the brakes are in such bad condition that the question is somewhat academic.

Derailers and gears have been around nearly as long as the bicycle, and the concept of the eliptical chainring is also far from new. It is one of those ideas that comes and goes and comes again http://www.sheldonbrown.com/biopace.html The basic design and functioning of the bicycle is unlikely to change much. We do have rather new additions like suspension, but that is more of a specialization than a general improvement: for riding down a mountain trail, it is a good thing. For normal riding it adds weight and adds flex to the drivetrain which wastes energy. There have been other "innovations" such as automatic transmissions for bicycles that provide little benefit versus the added complexity and weight and have therefore never caught on. Bringing the analogy back to the original topic however: Sayining that UNIX should be replaced with something entirely new just because it is 40 years old is like saying that the bicycle should be replaced with an entirely new technology just because it is 100+ years old. What you wind up with with that kind of thinking is something like the segway - It is much slower, heavy, expensive, has to be charged up, has a very limited range, depends on batteries which will wear out over time, etc. etc. Sure, the segway wins on cool and neat points, but pitted against the bicycle in terms of just plain utility, it doesn't stand a chance. Immagine someone trying to ride around the world on a segway :-)

If you bikers have problems being recognized by vehicle drivers on the road, I can heavily recommend driving with the lights on. Speaking for the traffic situation in Europe, all motorbikers are required by law to always have their headlights on day and night, vehicle drivers are a lot more sensitive to anything on two wheels if it has its headlights on.

Batteries add weight, generators add drag, but I think it's worth the effort. Because I personally dislike battery powered bike lights, I'd further recommend generator hubs, as they add a lot less drag than tire driven ones. You can write off both for increased muscle buildup, if you like ;)

There's a good summary on quality bike lighting here, please don't mind that it's a bit focused on two manufacturers - strong bike headlights switched on even at daytime can save some situations. Myself, I'd prefer hub driven generators anytime over tire driven or battery powered lighting, because I'm too lazy to recharge the batteries ;)

I don't want to contribute flamebait, I realize that it could be difficult at first, but if you take it slow and be consistent, you will find yourself in much better shape, with a higher energy level and (my favorite) the ability to abuse dessert more often without penalty.

Riding your bike can be great and I wish everyone would do it. If you want to make it a geek project, you can build your own and load the handlebars with a cool computer and HID lights to impress anyone. Good luck!

Nanodrive!

Take a suitably wide piece of paper. Lay it down on a carpeted floor.
Sit on it, and rock your pelvis forward a little.

Notice the two major depressions? Those are your pelvic bones. That is what you want to contact the seat.

Mark circles on the paper where the depressions are, and take it to a bike shop. Compare it against several seats.
Buy one.

Further info here.

In these times when bicycle Nirvana seems to be as many gears as possible or as hitech gear mechanism as possible I just *have* to post a link something that is the opposite and quite lotech, singlespeed: Singlespeed

I converted about a year ago, I'm on my second singlespeed now (the first one got stolen, wonder if the thiefs were surprised when they came to theur safehouse, or whatever, and discovered that they had stolen a MTB without gears...) and I absolutely will not go back.

I'd paste a link to my own homepage where you can read about my own conversion, but I don't want to risk it being slashdotted. You will probably find it on google (search for singlespeed + muuwiki if you are really interested).

This one is the Shimano NX-30, and it will power a 6 watt front headlight.

Maybe not as bright as your old 10-Watt, and sure, there is a little drag, but it's not bad, and you get to stop charging your bike lights for good. And $60 for the functionality of a battery *and* a front hub is a good deal.

spreer

It is true that many die hard MTB'ers ride Single Speeds, but there's always a freewheel/coasting capability.

Nope, he is right there are fixed gear bikes, they are usually used in velodrome racing, but they do make fixed gear mountain bikes too. See these articles for some tech info.

I could imagine a fixed gear mountain bike being very good in the mud, I know people like them for snow...

But I don't get down like that, I'm a roadie...

• Aluminum frames have a harsh ride

• Titanium frames are soft and whippy

• Steel frames go soft with age, but they have a nicer ride quality

• England's Queen Elizabeth is a kingpin of the international drug trade

This may seem like a pain, but fixies are actually extremely popular among a certain bike subculture, particularly urban bike messengers. The famous and wonderful Sheldon Brown has an extensive collection of articles on building and riding fixies.

This may seem like a pain, but fixies are actually extremely popular among a certain bike subculture, particularly urban bike messengers. The famous and wonderful Sheldon Brown has an extensive collection of articles on building and riding fixies.

I believe you're talking about "fixed gear" bikes rather than single-speed bikes. Single-speed means one speed, with or without a freewheel. Fixed gear is a fixed, non-freewheeled single-speed bike. As far as aluminum goes, its no harsher than any other frame material. The amount of flex offered by the frame, compared to the seat and tires is so small that, for a given frame geometry, I doubt many people could tell the difference between steel and aluminum. Steel's big advantage is that you can get it repaired in third world nations, and lugged steel frames look freekin' cool. Even the biggest retro-grouch of them all, Sheldon Brown, doesn't think steel offers significant comfort advantages: http://www.sheldonbrown.com/frame-materials.html

Admittedly, increases in bicycle technology have improved many aspects of the sport. However, at times it seems to interfere with the simple pleasure of riding.

A fixie removes the derailleurs and shifters. The drive train is direct drive. See Fixed Gear for the Road for many details.

Riding a fixed gear bicycle gives a unique riding experience, unadulterated by any technology issues. Without going into too much detail, it's extremely pleasurable to strip away some of the technology and really feel the essence of bicycling.

Plus, it's fun to think about someone trying to steal your bike!

Have you ever noticed how Segway boosters cite its stability and concomitant safety? Now, I'm willing to believe it's pretty stable, but it's time to point out the fallacy in assuming that implies safety, either for the rider or other users of public thoroughfares.

Unlike the skateboards in Snow Crash (which show N. Stephenson understood this issue far better than these fools) the Segway has NO RADAR. It can't tell if the rider is about to collide with something, like a person, pothole, or curb.

Why is that important? Well, for the other people on the pavement, it's mostly an issue of getting run into. For a Segway rider, though, I have yet to see anyone else point out the pothole and curb issue. Look at what you've got:
1) Much smaller wheels than a bicycle
2) A center of mass about as high, and not nearly as far behind the point of ground contact as a bicycle has.

Together, these mean that
A) Potholes, bump and curbs will stop a Segway much more forcefully than a bicycle
B) You can't stop a Segway nearly as quickly when you find yourself approaching one.

It's basic physics:
I) The smaller wheels, on encountering an object, have a steeper effective inclined plane
II) The torque about the point of ground contact when stopping is greater in the Segway, since the angle of force is almost perpindicular to it.

Given that stopping fast is already a problem with bicycles (here's how to stop a bicycle as fast as possible) since they can endo instead of skidding or ABSing like cars, it's going to be even worse for a Segway. I estimate that a Segway doesn't stop any better than rollerblades, and that's not too good.

I also think it likely a Segway can't turn away from trouble too easily either -- at least if it needs to keep both wheels on the ground.

Production shifted overseas before the plant was built in Mississippi. Giant was building their bikes long before that, and bikes were being imported from Japan in the 70's. Schwinn also dabbled in outsourcing some of their production in the early 80's to Murray, opened a plant in Hungary in the late 80's, as well as buying a third of China Bicycle Company. One of the most important factors in Schwinn's demise was technology, perhaps due to staff cuts in the R&D dept? Due to the change in materials used in producing bikes to more lightweight alloys, their manufacturing process would not allow the use of the lighter materials. See http://www.sheldonbrown.com/varsity.html for a primer on electroforging. IMO, because of the fact that their factory was behind the technology curve at the time, and the labor issues, Schwinn was doomed to fail for not closing their Chicago plant sooner. Schwinn became a relic, used in sales pitches as outdated, heavy pieces of antiquity by competitors. While Schwinn did ignore the MTBs until it was too late, a market segment that may have saved them, their bikes could never be confused with low-end bikes, and to this day their brand loyalty was enough for Pacific to buy the name even though the quality that made them who they were disappeared some 20 years ago.

How did that happen? Several factors: first, the third-generation family owners preferred to kick back and party rather than concentrate on the business. Even during the 1970s, the signs were showing. For a long time, they produced a line of lightweight, high-quality bikes in their Chicago plant, along with their heavier, mass-produced cousins like the Varsity. However, the utterly failed to promote them, and they were easily mistaken for the low-end bikes.

Meanwhile, out in California, people were taking old heavyweight cruiser bikes and fitting them with derailleur gears, and the mountain bike was born. Schwinn basically ignored this trend until it was too late.

Also, labor strife reared its ugly head. The Chicago factory was unionized, and the United Auto Workers decided that Schwinn workers should be paid on the same scale as GM, Ford, and Chrysler workers. Management's response was to build a plant in Mississippi, which turned into a complete boondoggle. Production eventually was shifted over to the Far East.

Schwinn eventually went bankrupt, and the pieces were picked up by vulture capitalist Sam Zell. Eventually, the Zell-operated version of Schwinn went bankrupt again.

It was picked up by GT, went on for a few more years, and went Tango Uniform yet again.

Now it is in the hands of Pacific Cycle, a mass-marketer whose products grace the shelves of department stores.

The only member of the Schwinn family who is still in the bike business is Richard Schwinn, who owns Waterford, an ultra-high-end manufacturer located in Waterford, Wisconsin. The factory, once upon a time, built Schwinn's high-end Paramount line. What a pity he didn't have the resources to buy back the name.

Every time I see a "Schwinn" in Wal-Mart, it sets my teeth on edge.

How did that happen? Several factors: first, the third-generation family owners preferred to kick back and party rather than concentrate on the business. Even during the 1970s, the signs were showing. For a long time, they produced a line of lightweight, high-quality bikes in their Chicago plant, along with their heavier, mass-produced cousins like the Varsity. However, the utterly failed to promote them, and they were easily mistaken for the low-end bikes.

Meanwhile, out in California, people were taking old heavyweight cruiser bikes and fitting them with derailleur gears, and the mountain bike was born. Schwinn basically ignored this trend until it was too late.

Also, labor strife reared its ugly head. The Chicago factory was unionized, and the United Auto Workers decided that Schwinn workers should be paid on the same scale as GM, Ford, and Chrysler workers. Management's response was to build a plant in Mississippi, which turned into a complete boondoggle. Production eventually was shifted over to the Far East.

Schwinn eventually went bankrupt, and the pieces were picked up by vulture capitalist Sam Zell. Eventually, the Zell-operated version of Schwinn went bankrupt again.

It was picked up by GT, went on for a few more years, and went Tango Uniform yet again.

Now it is in the hands of Pacific Cycle, a mass-marketer whose products grace the shelves of department stores.

The only member of the Schwinn family who is still in the bike business is Richard Schwinn, who owns Waterford, an ultra-high-end manufacturer located in Waterford, Wisconsin. The factory, once upon a time, built Schwinn's high-end Paramount line. What a pity he didn't have the resources to buy back the name.

Every time I see a "Schwinn" in Wal-Mart, it sets my teeth on edge.

Perhaps you are thinking of oval bicycle chainrings?

"Biopace is a patented non-round chainwheel design made and licensed by Shimano."

These car manufacturers are as ever, behind we chaps on 2 wheels. We've been running a Dawes Galaxy with embedded Debian (unstable) for years and it integrates brilliantly with Sheldon Brown's Geomagnetic Booster! ® to provide hours of stable open-source transport which is especially useful on a day like today when the London tube is on strike.

As ever with embedded systems, shoehorning all the code into the space available has been tough so we've fitted a specially adapted hub to the rear wheel and a windmill like fan on the rear sprocket to cool the Itanium 2 inner core. One advantage has been the thermic glow from this at nightime has reduced the need for rear-lights.

2 problems we're looking for volunteers to help with:
1) Seek-time latency on the hard-drive (also fitted to the rear sprocket and rotated by the chain) has been horrible and its been necessary to pedal really fast when playing mp3's
2) The kernel source is stored in the inner tubes / tyres and patching the source has been extremely haphazard with patches falling off, hissing air and rubber solution all over the place....

Next step is write kernel modules to drive Sheldon Brown's Bar-End Bayonetz to allow some much more aggressive Open Source advocacy, just as Cmdr Taco was requesting yesterday.

RMS is a big supporter of the Linucycle as we call it or the GNUcle as he prefers and is helping us in our efforts to integrate the Hurd kernel. An MS spokesman we contacted commented "This is just the sort of hippy s**t I'd expect from those Open Source guys...."

These car manufacturers are as ever, behind we chaps on 2 wheels. We've been running a Dawes Galaxy with embedded Debian (unstable) for years and it integrates brilliantly with Sheldon Brown's Geomagnetic Booster! ® to provide hours of stable open-source transport which is especially useful on a day like today when the London tube is on strike.

As ever with embedded systems, shoehorning all the code into the space available has been tough so we've fitted a specially adapted hub to the rear wheel and a windmill like fan on the rear sprocket to cool the Itanium 2 inner core. One advantage has been the thermic glow from this at nightime has reduced the need for rear-lights.

2 problems we're looking for volunteers to help with:
1) Seek-time latency on the hard-drive (also fitted to the rear sprocket and rotated by the chain) has been horrible and its been necessary to pedal really fast when playing mp3's
2) The kernel source is stored in the inner tubes / tyres and patching the source has been extremely haphazard with patches falling off, hissing air and rubber solution all over the place....

Next step is write kernel modules to drive Sheldon Brown's Bar-End Bayonetz to allow some much more aggressive Open Source advocacy, just as Cmdr Taco was requesting yesterday.

RMS is a big supporter of the Linucycle as we call it or the GNUcle as he prefers and is helping us in our efforts to integrate the Hurd kernel. An MS spokesman we contacted commented "This is just the sort of hippy s**t I'd expect from those Open Source guys...."

Also i rememember reading somewhere that in the Tour De France while riding downhill riders approach 100++kms and they have at that speed nothing but their skills to count on for brakes at that speeds tend to Jam.

I would call that kaka.

I have (on numerous occasions) pulled bikes down (with rim calipers) from 35-45 MPH in downhill situations, and from 25 MPH in a great hurry in traffic situations. I'd recommend the techniques detailed here (sheldonbrown.com) by Sheldon "FrontBrake" Brown.

I also don't scrimp on my brakes, using the old Campagnolo Record stuff that's hardly available anymore, and taking the time to rig them properly. Also recommended are Scott Mathauser's best brake pads. I would feel confident with these brakes at 60MPH, and I know the racers have even better equipment. Heck, at 100KPH (=62MPH) just untucking and sitting up straight will take off about 10MPH right there. They _have_ braking control on those downhills, they just don't win races by using it. To brake a bike from 80MPH (if I were in a hurry, which a speed-trialer is NOT) I might want the nice disk brakes which I see on downhill rigs.