Showing posts with label old designs. Show all posts
Showing posts with label old designs. Show all posts

01 June 2017

Without Cotters, But Not Cotterless?

The French firm Specialites TA is probably best-known for its Pro Vis 5 crankset, often called the "Cyclotouriste" (though TA itself never used that name). Even if you've never ridden one, you've almost surely seen it:




It may well be the most versatile crank ever made:  The outer chainring, which bolts on to the inner bolt circle (the one closest to the center of the crank), were available in  sizes from 40 to 64 teeth.  The middle and inner rings, which bolted to the outer ring, were available in sizes from 26 to 50.  You could bolt one or two rings to the outer ring--or ride just the outer ring as a single.  So it may well be the only crankset that ever was truly designed to be used as a single, double or triple.  (On Vera, my Mercian mixte, I use a Shimano Deore MT-60 triple crank by substituting a BBG bashguard for the outer chainring.)  

Also, it may be the only crank that spawned as many imitations as the classic Campagnolo Record:  Sugino made a crankset that looked like a TA with a satin rather than a polished finish, and an early Shimano Deore crankset had the same bolt pattern, if a different look--as did the Stronglight 49D, the crank I'd probably choose if I wanted one with the 50.4 mm bolt circle and the option of single, double or triple.

Anyway, from the time it was introduced in 1963, the TA Pro 5 Vis became the crankset most commonly used on custom and other high-end touring bikes, particularly tandems, for about a quarter of a century.  Even early mountain bikes sported these cranks because they offered such a wide range of gearing--and, in spite of their appearance, were actually all but unbreakable.

Before Specialites TA introduced the Pro 5 Vis (five-bolt professional), the company produced chainrings used on cranks by other manufacturers.  Founder Georges Navet--who started out with ill-fated front-wheel drive experiments (hence the name:  TA stands for traction avant) wanted to produce a crankset to rival the best ones made by Campagnolo and Stronglight.  




Although Stronglight had been making cotterless cranks--fitted to the familiar square-taper  bottom bracket axle, which they originated--since the 1930s, some were still skeptical about the design.  Track racers were still using cottered cranks into the 1960s and some tourists still feared being stranded somewhere because the local garage or machine shop didn't have the right tools.  Other cyclists simply didn't want to change.




So, Monsieur Navet came up with a crankset that has the same arm and chainring bolt pattern we see on the Pro 5 Vis.  Unlike the Pro 5 Vis, this crankset--called the Criterium--was not cotterless.  So, in following the logic of cycle componentry from that time, you might say it was a "cottered" crank.  And you would be right--sort of.





If you didn't look closely, you might mistake them for cotterless cranks--which they are, sort of.


Specialites TA Criterium cranks with Spence Wolf-modified Campagnolo Nuovo Record rear derailleur, 1969.  From Velo Vecchio.


OK, you ask...What are they?  Well, the cranks were held to the axle by a bolt with an allen key head on one end, and a nut that threaded on to the other end.  That made the "cotters"--and the cranks easier to remove than those of traditional cottered cranks, and didn't require a special extractor, as cotterless cranks require.

An engineer once told me that the bolt holding the Criterium crank to its axle is technically not a "cotter", but rather a "pinch bolt."  The reason, he said, is that the traditional cotter has a wedge cut-out that is force-fit (usually by hammering) onto an axle with a flat spot.  The force--or stress, if you will--is what holds the crank to the axle.  On the other hand, the bolt in the Competition bore no such stress, and it merely holds the arm in place on the nearly pear-shaped axle end. 

The "not-cottered-but-not-cotterless" design had its advantages, in addition to not requiring special tools.  For one, the bolts were less prone to breaking or stripping than traditional cotter pins.  For another, it allowed 4mm of lateral movement in either direction on the axle.  That allowed the crank to be positioned for the best possible chainline.


One further advantage was that the design allowed the cranks to be made from aluminum.  A few companies made aluminum cottered cranks, but nearly all of them broke outright or ended up so gouged that the cotter pins could no longer hold them on to the bottom bracket axle.  But, because the Criterium's pinch bolt did not need hammer-blow forces to attach them, and because the shape of the axle and the way the bolts fitted into the crank provided an inherently more secure attachment, there was little to no danger of breaking or gouging the cranks.

What that meant was that the Criterium was, at the time it was introduced, the lightest crankset on the market.  It weighed even less than the alloy cranksets from Stronglight and Campagnolo because the Criterium's design allowed it to be made with skinny arms, like cottered cranks, and thinner around the axle interface.  it almost goes without saying that the Criterium was lighter, by far, than any other crankset because most--besides the aluminum cotterless sets made by Campy, Stronglight and a few other companies--were made of steel.


Cinelli Super Corsa with the drivetrain shown in the above photograph.  Also from Velo Vecchio.


The Criteriums were, like most Specialites TA products, meticulously made and beautifully finished.  Spence Wolf, the owner of Cupertino Bike Shop (one of the first in the US to devote itself to high-end bikes), equipped a few of the Cinellis and some of the Alex Singer bikes he sold with these cranks when the customer wanted wide-range gearing.  He would pair the Criteriums with a Campagnolo Record rear derailleur he modified with a long pulley cage he made for it.




But Specialites TA didn't make Criteriums for very long.  They introduced the Pro 5 Vis only a couple of years after the Criterium and, by that time, most dedicated, high-mileage cyclists--even track racers and tourists venturing into remote areas--were convinced that cotterless cranks were indeed a superior design.  To use a cliche, the rest is history.

Note:  I have seen only one of these cranks in person, on a bike I tuned up when I was working at the Highland Park Cyclery.  The bike had no markings on it, but the customer said it was "built in France".  I don't think it was a constructeur bike, but it looked fairly high-end.

23 February 2016

The Gear Maker

During the 1970's Bike Boom, millions of Americans bought ten-speed bikes.  Many people rode them only a few times, or once.  Some didn't like the dropped handlebars or small "hard" seats; others couldn't quite get the hang of shifting derailleurs.  Given the fragile nature of most derailleurs of the time, the results weren't pretty, especially when the derailleurs were out of adjustment or the rider tried to shift while standing still or under pressure.

Then there were the engineering types and tinkerers who look at any mechanical device and think "There must be a better way."  And, finally, there were lots of newly-minted lawyers with too much time on their hands who saw all sorts of potential lawsuits lurking. (Some of them helped to found the CPSC.)

One of the best-remembered attempts to correct the "deficiencies" of derailleur gearing was Shimano's Front Freewheeling system.  Basically, it incorporated a freewheel-like mechanism between the chainrings and crank so that the chainrings spun as long as the wheels were spinning. This allowed riders to shift without pedaling. 

Some people who were accustomed to internally-geared hubs (like Sturmey-Archer three-speeds) liked this new innovation, which is probably the reason why it developed something of a following in Germany, where many people still cycled for transportation but few were accustomed to derailleurs.  However, the FF system was heavy and complicated, and was equipped only on entry-level bikes.

Another attempt to bypass the idiosyncrasies of derailleurs and multiple rear sprockets is all but forgotten today.  But it was interesting in its own way.

Before its foray into the bicycle business, Tokheim had about seven decades' worth of experience in manufacturing fuel dispensers and pumps, and equipment for payment terminals and retail automation systems.  So, if you've ever owned or managed a gas station, you've seen or used Tokheim equipment.

Like a few other American companies, Tokheim thought the Bike Boom was an opening for a new profitable market.  And, like those other companies (including, of all companies, Beatrice Foods!), they thought they could make bike parts and accessories even though they had absolutely no experience with them--or, it could seem, cycling. 

Then again, Tokheim's experience with pumps and other kinds of machinery had, it would seem, at least some applicability to designing and manufacturing a bicycle gearing system.  It was at least somewhat in evidence in their "Gear Maker" system.

The Tokheim Gear Maker


When drivetrains with derailleurs are shifted to their extreme positions (small chainring with the smallest rear cog or largest chainring with largest rear cog), severe chainline angles can result.  This usually results in noisier running; in worse cases, it leads to premature chain and cog wear.  In the worst cases (especially with an inexperienced and unskilled rider), the chain can be thrown off the cogs and into the wheels or get stuck between the chainrings and chainstay.

Most cyclists learned, in time, not to shift into the extreme gear positions--or to do so carefully.  However, some could never get past that first experience of a missed shift.  Or, if they had no previous experience with multi-cog systems, they were intimidated.




That is the "need" the Tokheim system was intended to meet.  Imagine an old-fashioned Ferris wheel:  the kind with a "spider" that rotates around an axle at its center and "cars" or "gondolas" at the end of each arm.  Those cars and arms are in fixed positions and will always reach the same height at the peak of their rotation. 


Now imagine that between those arms, there are other arms, except that these arms are expandable and retractable.  Thus, the Ferris wheel operator could expand the diameter (and height) of the wheel for more adventurous customers.  But the cars of those expanded and contracted cars would rotate in the same plane as the cars on arms with fixed lengths.







The gear in the "gear maker" was like that Ferris wheel.  It was operated with a twist-grip shifter.  When the shifter was in its "high" position (slackened cable), the chain ran on the smallest gear, which was fixed to the axle.  Shifting down made an interposer arm push a series of bars out successively.  At the end of each bar were teeth like those of a typical rear sprocket.  The chain ran on a larger sprocket something like the "skip tooth" cogs found on some 1970s freewheels.  A tensioner--basically a derailleur cage and pulleys--took up chain slack.

For a time, the Tokheim system came as standard equipment on a few Huffy and Murray bikes.  I never saw a bicycle sold in a bike shop that was equipped with the Tokheim system, and I don't know whether anyone ever retrofitted it to a bike.  For that matter, I didn't know anyone who rode it, and only got to work on a couple of them, so I don't know how they performed in the "real world".  However, as the gears were made of plastic, I suspect they wore fairly quickly.  And, as Tokheim stopped making it around 1980 and, to my knowledge, never offered replacement parts (and because most of the bikes that came with them have long since ended up in landfills), I don't suspect that very many Tokheim Gear Makers are in use today.  But, I think, they are interesting nonetheless.

10 August 2015

Nonpareil: Nothing Like It, Ever

For many years, my favorite candy was the chocolate nonpareil.  During my childhood, they usually came on waxed-paper sheets.  I think part of the appeal (pun intended) of the nonpareil was peeling it off the sheet.  It was sort of like pulling a button off a shirt.

I haven't eaten those candies in years.  Now I see they're sold in little bags for about five dollars.  I'd probably like them if they were made from really good dark chocolate, which would be a nice counterpoint to the sugar pearls that coat them.

(I've often wondered whether I'd like some of my other favorites from childhood--like Nestle's Crunch and Kit Kat--if they were made with high-quality dark chocolate. The dark-chocolate Kit Kat that's sometimes sold in the US seems to be just a Hershey bittersweet bar with wafers in it.)

Back when my grandmother was bringing those sheets of nonpareils, I didn't know any French.  Later, I'd learn that "nonpareil" means "without parallel"--or, if you like, "There's nothing like it", which is how I probably described my favorite candy at one time or another.

Perhaps I shouldn't be surprised that this is also called "nonpareil":

 

The Classic Cycle website describes it as "the missing link in the evolution of the bicycle".  Apparently, it was built around 1890, after bike makers moved away from the "hobby horse" design and had been making "penny farthings" (high-wheelers) for a decade or so.  

The Nonpareil seems to have been one of the first bikes with wheels of equal size.  Most likely, it's also one of the first chain-driven bikes.  I must say, though, there's nothing remotely like its chain on modern bikes:

 

For that matter, there's nothing like that frame, either.  Given that everything that's been done (in bike design, anyway) gets done again,  I have to wonder whether someone's designing a frame with a single tube that slopes from the front to the rear stays.  It eliminates the top or down tube, depending on how you look at it.  Can you imagine how much weight that saves?  I'd bet that, rendered in carbon fiber, such a frame could be built into a complete bike that weighs less than 5 kilograms.

Of course, unless the UCI changes its rules, no racer could use such a bike in competition.  But someone would want it anyway just because it's, well, nonpareil.

 

P.S.  I'd love to find the oil lamp that fit on the fork.  There's definitely nothing like it made today! 

01 November 2013

Everything New Is Old Again

Early in this blog's history, I documented using, at the suggestion of my gynecologist, Terry "donut" saddles.  I found that I didn't like them:  They reminded me of the Avocet saddles with the "groove" in the middle, which I tried not long after they came out.  Both saddles had the same effect:  They created pressure points, and discomfort, around my genitals--even though my genitals were not the same when I rode the Terry as they were when I rode the Avocet.

After the Terry experiment, I went back to Brooks saddles and have had no problems.  That may have something to with my post-surgery genitals healing and developing:  Although the area around them is more tender than it was in my days as a male, it's not quite as delicate as it was in the days just after my surgery.

Brooks has been making stretched leather saddles for nearly a century and a half.  Over the past decade or so, other companies have begun to make similar saddles.  At least even the most casual cyclist knows that those companies are appropriating and,in some cases, tweaking an old technology.  

The same was not true when Avocet first came out with its "grooved" or "double hump" saddles in 1977 or when Terry came out with its "donut" seats in 1994--or, for that matter, when AnAtomica started cutting out the middle sections of Brooks saddles in 2005 (or when Brooks began to sell its "Imperial" saddles in 2008. Every one of those ideas had been tried before.  Those companies marketed those saddles--and the public believed they were--innovations. 

Take a look at this Garford ladies' padded saddle from 1895:




Or this one, introduced five years earlier:

 


Yes, that is the original "Imperial" saddle, in the Brooks 1890 catalogue.