Showing posts with label pneumatic tire. Show all posts
Showing posts with label pneumatic tire. Show all posts

27 April 2017

Riding On Air--Or Full Of Hot Air?

When I first built my Bontrager Race Lite frame--my Christmas present to myself in 1995--I installed a Rock Shox Mag 21 fork because that was what I had.  Within a few months, though, I'd replaced it with a Rock Shox Judy SL.  Even if you weren't a mountain biker--or on this planet--back then, you've probably seen the Judy SL, with its distinctive yellow finish, in person or images.



It was a great fork, at least for a few rides.  It suspension consisted of a Monocellular Urethane (MCU) spring with a hydraulic damping cartridge.  MCU, like "carbon fiber", shows the power of words or, more precisely, marketing:  Both terms entice people to fork (pun intended) over large sums of money for plastic.

To be fair, though, the hydraulic damping cartridges weren't much sturdier than those springs.  Neither one stood up to sustained punishment, something I could inflict on a bike even in those days, when I was skinny.  

I would soon find out, though, that my springs and cartridges weren't failing because I was a particularly hard-charging rider, as much as I fancied myself as one.  Other mountain bikers were having similar experiences.  In fact, I even witnessed riders losing their suspension in the middle of rides or, worse, jumps.  

Some of those riders switched to other suspension forks, like those from Manitou and Marzocchi.  On the other hand, other riders--including yours truly--retrofitted their Judy forks with Englund air cartridges that we kept inflated with tiny pumps that had needles like the ones used to fill up basketballs and soccer balls at the ends of them.

Those air cartridges were far more durable and were smoother than elastomers (especially when they got dirty) or other kinds of suspension.  It makes sense when you realize that what is arguably the first successful kind of suspension for bicycles (or wheeled vehicles generally) ever made is the pneumatic tire.

Hey, it's not for nothing that we have the phrase "like floating on air" to describe a smooth ride.

With that in mind, I can't help but to wonder how this bicycle would ride:







What I am about to tell you is not a joke:  The bike is inflatable.  Yes, the bike.  

Its frame consists of a series of rubber tubes connected by valves.  This system is supposed to help keep the bike rigid while it's ridden.  The seat stays (or, as the psfk article calls them, the "tubes connecting the seat and back wheel") can be adjusted to give a softer or harder ride.

In case you were wondering:  The rubber tubes were designed with a Kevlar sheath which, according to the bike's designers, make it difficult to cut and help to support the rider's weight.

The bike is designed so that when it's deflated, it will fit in the storage boot of a car.  So, perhaps, it won't surprise you to learn that the bicycle was designed by Ford engineers.

Henry Ford was a bicycle mechanic and, even in his seventies, took "a three mile spin every evening after supper," according to a Time magazine article.  I wonder what he would make of this inflatable bike.

06 January 2017

I Love Tires, Too!

Last week, I mentioned John Boyd Dunlop, the inventor of the pneumatic tire.  It is, without a doubt, the single most important innovation in the history of cycling--and one of the most important in the history of technology.  

Supposedly, he invented it to appease his son, who complained about the harsh ride of the tricycle he'd just received for his birthday.  


If that story is true, let's hope the son's reaction is something like this:


11 February 2016

They Didn't Come As A Shock Then...

Writing recently about "path racers" and the mountain bike experiences of my youth got me to thinking of just what it means to be a "mountain" or "path" rider--and what makes bikes suitable for those kinds of riding.

I also got to thinking about how and when those kinds of riding came to be seen as distinctive from other kinds of riding, and how the terms to describe them came to be.

It seems to me that those kinds of cycling and bikes--as well as cyclo-cross and bicycle motocross (BMX) evolved as specialties within cycling because of paved roads. 

Think about it:  In the early days of cycling, there were few paved roads.  And the few paved roads had gravel, cobblestone or granite sett (a.k.a. Belgian Block) surfaces. Thus, most of the time, cyclists were riding under conditions that, today, we would equate with off-road or cyclo-cross--or what the Brits would call "rough stuff".

If you are a mountain or cyclo-cross rider, try to think of what your rides would be like with solid rubber tires--or no tires at all. In other words, think  of what it would be like to ride your favorite trail on bare wood or metal rims. That is, I believe, what normal riding conditions would have been like for most cyclists before the pneumatic tire was invented in the late 1880's.

And to think cyclists rode, not only without the cushioning of air-filled tires, but on front wheels that were almost as tall as the riders themselves!

So, really, it's not surprising that there were attempts to incorporate suspension into bicycles. 




This Blackledge bicycle, patented in 1890, uses a spring in the fork assembly to soften the blows from the rough roads of the day.  It seems that ever since the "safety" bicycle (two wheels of more or less equal size) was invented, attempts to incorporate suspension into bicycles began with the front fork.  For one thing, we feel road shock first at the front.  For another, shock to the front is more likely to upset our balance or momentum--and cause crashes-- than shock at the rear.

This Tillinghast bicycle, patented the following year, has another interesting front suspension system as well as a unique kickstand built into the pedals:



Still, attempts to soften the ride--and make the bike more stable on rough surfaces--weren't limited to tinkering with the front end.  Here is a drawing submitted by Fernand Clement for the suspension bike he patented in 1892:





Here is another early rear suspension system on a J.H. Mathews bicycle, patented in 1891:




Hmm...Wouldn't it be fun to envision Messrs. Blackledge, Tillinghast, Clement and Mathews showing up at Tamalpais a century after they created these bikes...but just before Rock Shox, Marzocchi, Manitou came along?

18 March 2015

Another Celt Blazes A New Path For Cycling--And Everyone

Now, on the day after St. Patrick's Day, I'm going to talk about another Celtic person in the world of cycling.

Unlike Sean Kelly, this person was from Scotland but lived in Ulster (a.k.a. Northern Ireland).  Another difference is that this person I'm about to mention never won any Tour jerseys or classics.  In fact, as far as I know, he never raced at all.  

But we should all be grateful to this person, who invented something that not only revolutionized (in every sense of the word) cycling, but the whole world. 

That last clue may have tipped you off.  Yes, this person's invention had to do with the wheel.  No, he didn't invent the wheel:  That came a few millenia earlier.  But what he did made the wheel--and the bicycle--versatile in ways no one could have previously imagined.

What's just as interesting is that this person not only was not a racer, he wasn't an engineer or a technical person.  In fact, he was a veterinary surgeon at the time he invented the thing I'm going to mention.



Early Pneumatic Bicycle Tire
Early pneumatic tire.  From Dave's Vintage Bicycles


That thing was...the pneumatic tire.  Without it, bicycles are no faster than horse-drawn carriages--and wouldn't be able to traverse some of the terrain our bovine friends have trod for milennia. Ditto for automobiles:  They would have been all but useless, especially given the road conditions of around the time the gasoline-powered engine was invented.  And aircraft, at least as we know them, could not take off or land.

image of John Boyd Dunlop
John Boyd Dunlop

 The man in question is John Boyd Dunlop.  As the story goes, his young son was prescribed cycling as a cure for a heavy cold.  Given the relative cost of bikes at that time, it took a pretty fair amount of audacity to complain that his tricycle--with hard rubber tires on iron wheels-- was uncomfortable.

No one knows exactly how Dunlop pere came up with the idea of bonding canvas together with liquid rubber to make an inflatable tube.  But he did and in 1888 he patented the idea--and, in the process used the word "pneumatic" for the first time.  

A local firm, W. Edlin and company, agreed to make casings for the new tubes and the following year, a well-known cyclist, Willie Hume, used the new tires to win a race at Cherryvale.  A paper manufacturer who was one of the spectators would buy Dunlop's patents a few years later.  By that time, he had moved to Dublin, where he manufactured bicycle frames in collaboration with a local firm, Bowden and Gillies.