A Brief History of Dura-Ace

The stories behind five revolutionary derailleurs that helped everything to click into place for nifty shifters Shimano.

Crane, 1971

Crane, 1971

Shimano fought against stereotypes during the early ’70s when Campagnolo dominated the pro racing scene. The Italian marque’s name was synonymous with quality and durability; everything else was fragile and not to be trusted.

For Shimano to upend that narrative meant a minor miracle. Enter a new derailleur, forged from aluminum and named for elegance in motion. Shimano’s Crane derailleur was arguably the most significant driver of the Dura-Ace legend — and it wasn’t even a Dura-Ace derailleur.

The Crane moniker attached to Shimano’s then-top-end derailleur per- haps didn’t help matters; birds are certainly graceful, but bring fragility to mind. Yet the Crane derailleur was a forged aluminum component with a dropped parallelogram design and a high quality finish. “The aluminum forging and finish were equal to that of the Campagnolo Nuovo Record, the top derailleur of the time,” says Mike Sweatman, founder of Disraeli Gears — probably the most comprehensive derailleur reference website around.

The dropped parallelogram design meant that the derailleur pulleys remained parallel to the cogs as the rear mech moved across the cluster of gears. The Crane de- railleur was Shimano’s first big strategic move against the big players of the day, and it proved Shimano could create a better derailleur than Campagnolo and its European competition. But rival brand SunTour still had an advantage: the slant parallelogram.

This design allowed the derailleur to move across the cassette laterally, like a drop parallelogram derailleur, and to move up and down relative to the size of the cog in the cassette. In other words, the top pulley of the derailleur was always close to the cog, regardless of cog size, which made for smoother, quicker and more re- liable shifts.

Despite SunTour’s superior design, Shimano caught a break when Schwinn adopted the Crane. “Schwinn was a huge player in the US market, and very influential in the cycling world,” says Sweatman. “Schwinn had been making a top-end touring model fitted with the Campagnolo Gran Turismo derailleur. This was a hideous steel object that weighed a ton and changed gear spectacularly badly. Schwinn decided that enough was enough and replaced the Gran Turismo with a long-armed Shimano Crane.

”The response from dealers and consumers was overwhelmingly positive. This did not escape Campagnolo’s notice; the Italian brand countered with its own derailleur to match the Crane, but with its notorious Italian styling. The powerhouse drivetrain manufacturer fully expected Schwinn to dump Japan and return to Italy, so to speak. But Schwinn felt the Crane was the better model and stuck with Shimano.

This coup gave the Japanese company a David-versus-Goliath victory. The Crane really took off, and major winds were starting to shift.

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Dura-Ace AX-7300, 1980

Dura-Ace AX-7300, 1980

In today’s superbike era, it’s hard to believe that aerodynamic design of any significance could play a part in derailleurs. Yet that’s exactly what Shimano set out to accomplish with the Dura-Ace AX-7300 groupset, refining every component in the groupset. And it was both a revolution and a side step.

The finished product was a sight to behold, and it included an indexing system. Shimano had led other manufacturers into a new era, and everyone else was forced to play catch-up.

That meant new styling and refinements across the board for every brand. “Shimano’s cash-strapped competitors spent millions smoothing off the corners of derailleurs and making new tooling to manufacture the new shapes,”says Sweatman. “And Dura-Ace AX also established a new technological pecking order.”

Shimano essentially surpassed SunTour’s well-documented role as R&D masters, which cemented their place as the undisputed technology leader. Once again, David was making several Goliaths very nervous.

Yet the Dura-Ace AX-7300 groupset was not a big success for Shimano. The new look and feel divided opinions, and the indexing, as with other early attempts at the technology, was not totally reliable.

It seemed Shimano had made a mistake, yet forcing the hands of the competition ultimately worked out in the company’s favour. This marked a turning point for the company’s marketing as well. Gone were bird names that elicited images of fragility. The name Dura-Ace evoked strength and quality; Dura came from the duralumin — an aluminum alloy — used to construct the derailleur. And Ace conjured images of the top, the pinnacle. It was an insight into Shimano’s future intentions: to become the best of the best on every race bike in every peloton.

Dura Ace 7400, S.I.S, 1985

Dura Ace 7400, S.I.S, 1985

Everything clicked into place when Dura- Ace 7400 launched – literally. While Shimano’s previous cracks at an indexed shifting system had been unreliable, much like its competitors’ attempts, Dura- Ace 7400 ushered in the Shimano Index System (S.I.S).

At the time, friction shifters still ruled the day. Index systems had come and gone, fading into obscurity due to unreliability. But Dura-Ace 7400 was the first that worked well and changed all that. “It was slick, reliable, and long-lasting – an under- stated triumph,” Sweatman says. “From this point on, the future of gearing was clearly indexed.”

The timing could not have been better. SunTour’s slant parallelogram patent had run out, so Shimano created its own version to pair with its S.I.S. system. A force to be reckoned with: quicker and smoother shifting that clicked into place without having to coax the chain into gear – a major breakthrough.

While the Dura-Ace 7400 derailleur was a beautiful piece of machinery, it eschewed some of the aerodynamic touches that Shimano had tried in vain to make stick for the last several years. The more conventional look went a long way towards convincing the more conservative-minded riders to give it a go.

It is notable, too, that Shimano scored a massive win when a competitor’s patent ran out. Perhaps this was the moment that the company recognised the outsized value in patents, going on to become notorious for its use of them – not only for products it intended to bring to market, but also for those that never saw the light of day. The latter helped protect Shimano from its rivals in a new way: by making them design around concepts Shimano had al- ready considered, paying dividends for decades to come.

Dura-Ace 7970 Di2, 2009

Dura-Ace 7970 Di2, 2009

Think of how many legendary racers came and went between 1985 and 2009. Dura-Ace changed with the times of course, but the next big revolution in shifting came a long time after S.I.S. changed the shifting game in Greg LeMond and Laurent Fignon’s era.

Shimano still had to fight Campagnolo, which dominated sponsorship at the pro level. Andy Hampsten won the Giro d’Italia in 1988 using a Dura-Ace groupset, and a World Championship win arrived three years later with Gianni Bugno. Those victories helped Shimano on its journey to dominance, but it was not there yet. 

Shimano made plenty of inroads in the ’80s and ’90s and Dura-Ace arguably had little to do with it, at least financially. Success on the balance sheet came largely through Shimano’s dominance on mass-market bikes and less expensive, consumer-focused rides. All the while, they virtually owned the entirety of the mountain bike market, with SRAM playing the underdog role off-road.

On it, however, Shimano’s true dominance was cemented in 2009 when it electrified the bicycle market with Di2. “Dura- Ace 7970 was the first real statement that the future was unquestionably electronic,” says Sweatman.

Dura-Ace 7970 was Shimano’s first Di2 (Digital Integrated Intelligence) system at the top of the line. The company had executed Di2 on the Nexave groupset eight years earlier, but it did not gain much traction, especially among racers. 

Mavic had also given electronic drivetrains a go with the Zap derailleur and later the wireless Mektronic, but both systems were plagued by consistency and changing-speed issues. Campagnolo also toyed with prototypes for years. But Shimano meticulously designed its electronic system to not only beat Campagnolo to market, but get the technology right the first time. It had to be fast, reliable and, ultimately, impeccable. And it was.

Some cynics initially derided Di2 as unnecessary or gimmicky. But racers saw the value, as is often the case when one rider wins on new technology and the others are left wondering what they are missing out on.

Di2 swept through the bike world with a vengeance and became the race bike stand- ard over the course of the next several years. While more conservative old guard racers stuck with cables, up-and-comers and future legends grew into the sport with batteries, wires and the lightning fast shifts that came with them.

There was no turning back. Shimano had ripped the spotlight away from Campagnolo with its Di2 system, and the electric future arrived with Shimano as its flag-bearer. By 2019, a decade after the first Di2 system and a host of revisions and refinements to the electronic system, ca- ble-actuated drivetrains in the pro peloton  became quaint novelties reserved for the most traditional riders.

Dura-Ace RD-R9250, 2021

Dura-Ace RD-R9250, 2021

Engineering often feels like a series of false summits. You reach the top of one only to see there’s still further to climb, yet more advances to make. Such is the case with Dura-Ace and its brand new iteration that launched in August 2021.

After SRAM launched eTap in 2015, ditching wires altogether to create the first  truly reliable wireless shifting system, jour- nalists, fans, and racers besieged Shimano  with the question — will you do your own wireless drivetrain? The Japanese brand simply pointed to the success of the Di2 system. The years ticked by and the wires remained.

Dura-Ace R9200-series represents Shimano’s arrival at yet another summit. The RD-R9250 rear derailleur integrates a wireless unit, charger and switch inside the body to create an adaptable, fast and powerful shifting brain.

The R9200 system still uses wires to connect the front and rear derailleurs to a large central battery in much the same way earlier Di2 systems worked, largely to ensure the longest battery life possible. But the shifters communicate with the rear derailleur wirelessly, eliminating any hard- wired connection to the derailleurs and batteries. Shimano has officially entered the wireless era.

The derailleur cage is long enough that riders of yesteryear might have mistaken it for a mountain bike rear mech, such has been the drastic change to gearing over the years. The RD-R9250 can accommodate up to a 34-tooth cog in the cassette, a number unimaginable only a few short years ago.

One of Shimano’s core claims with the RD-R9250 speaks to how far the technology has come in recent years. The new derailleur, they say, is 58 per cent faster than the RD-R9150 that came before it, itself setting a benchmark for quick shifting. In a sport driven by the most marginal of gains, you can bet it will be popular with pro racers.

Shimano is in the drivetrain driving seat once again. Whatever next? Watch this space...

Illustrations by Jorge Faes Ruiz & produced in association with Shimano.