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Women's Specialized S-Works Tarmac SL6: Launch and first look

30 Jun 2017

A bike for people not genders. Is this the end of the road for women’s specific bike geometry?

Any discussion of women’s specific bikes has the potential to descend into an ugly, Brexit-style spat. On one side are the believers, who endorse the idea that bikes should be modified to fit the anatomy of the female form. Equally vociferous are the deniers, who will argue that bike geometry should not, ever, discriminate by gender.

The women’s-specific movement gained traction in the late 90s when brands, including Specialized, began using anthropometric data to inform their product development.

The data suggested that women were shorter than men, with longer legs, shorter torsos and shorter arms.

To accommodate these attributes, it was concluded that women needed bike frames with a shorter reach and taller stack (front end).

And so, in 2002, Specialized launched the Allez Dolce and Allez Vita – their first women’s specific bikes.

The Amira, unveiled in 2009 alongside the all-new Tarmac, sat at the top of Specialized’s women’s specific tree. It was a fast, stiff, crit-loving race bike for women, and it had proven pedigree – most notably as Lizzie Deignan’s World Championship-winning bike.

It was the women’s equivalent to (but not version of) the ever-popular men’s Tarmac, but now the Amira is no more.

In its place is the Women’s Specialized S-Works Tarmac SL6, a unisex frame with women’s specific touchpoints, featuring a shared geometry, designed for cyclists not genders.

A new approach

When Specialized acquired Retül in 2012 it gained access to over 40,000 data points taken from the bike fits of men and women.

Analysis of this data threw up some surprising results, which encouraged Specialized to hotfoot it back to the drawing board.

‘When we compared men and women of the same height we realised that some differences were, in fact, not statistically significant.

For example, the average women’s leg length and the average men’s leg length were not as different as we previously thought,’ says Stephanie Kaplan, women’s road product manager.

What’s more, Retül’s data showed that the men and women riding the Tarmac and the Amira were, in fact, setting up their bikes in a similar fashion.

For these women riders – ones who raced or rode aggressively – the notion of needing a shorter reach and taller stack simply wasn’t true.

Kaplan adds, ‘We also realised that the geometry of the Amira had gravitated towards that of the Tarmac and that the differences were no longer sufficient to necessitate two different ranges.’

But that’s not to say that women are now just riding the old Tarmac. Both bikes have changed.

‘The new Tarmac is an all-new performance geometry for people,’ says Chris Yu, director of integrated technologies.

Compared to the Amira, the changes in geometry are significant, especially on the smaller frames.

The new Tarmac SL6 is longer in the top tube (562mm compared to 547mm in size 56cm) and has a taller stand-over height (795mm compared to 777mm).

The shorter wheelbase has got even shorter (985mm from 994mm) but the seat angle stays the same at 73.5°, all of which results in a snappy ride.

The new Tarmac

The Amira was a thing of beauty – a rare example of a true racing bike designed for women. But eight years is a long time and it was almost certainly time for a change.

Initially, in the UK the new Women’s Tarmac range will feature only the Women's S-Works Tarmac SL6 and the Women's Tarmac Expert, although the range will expand in the future.

Five sizes are available from 44cm to 56cm, with crank lengths ranging from 165cm to 172.5cm.

Advances in carbon technology and the science of aerodynamics mean that the new Women's S-Works Tarmac SL6 is undoubtedly a stiffer and lighter bike than the Amira.

The new Women's S-Works Tarmac SL6 weighs 733g for a 56cm frame and the total bike weighs around 6.48kg. By comparison, a 56cm Amira S-Works SL4 weighed in at around 6.7kg.

There are some radical, performance-driven differences too. Gone are the flared, cobra-shaped top tube, the bulbous head tube and the chunky down tube.

The new frame features a smaller, more refined main triangle, and has introduced some aero attributes from its wind-slicing brother, the Venge.

These include bladed seatstays that join the seat tube some way below the seat clamp, and a ‘D-shaped’ seatpost.

The seatpost itself features two different carbon layups, making it more flexible nearer the top for comfort, and stiffer at the point where it enters the frame.

For the spec, the S-Works Tarmac SL6 comes with Dura-Ace Di2, paired with a Specialized S-Works crank.

The Roval CLX 50 wheelset is light at 1,400g and aero with its 50mm carbon rims. To find a set of wheels that retail at £1,870 specced as standard is fairly remarkable, even for a bike that costs £9,000.

There’s clearance for up to a 33mm tyre, although the bike comes specced with 26mm Specialized Turbo Cotton tyres.

The women’s specific components include the Oura Pro 155 saddle and S-Works SL Carbon Shallow Drop, well suited to smaller hands.

The Women's S-Works Tarmac SL6 is a revolution in bike design for women, and men. It’s a simple idea – bikes should work regardless of gender – but Specialized’s execution is excellent.

Hearts may be broken at the news that the Amira is gone but there’s something to love in its place.


Frame S-Works Tarmac SL6, FACT 12r carbon, Rider-First Engineered™, OSBB, full internal, electronic-specific routing, internally integrated seat clamp, 130mm rear spacing
Fork S-Works FACT carbon
Stem S-Works SL, alloy, titanium bolts, 6-degree rise
Handlebars S-Works SL Carbon Shallow Drop, 125x75mm
Tape S-Wrap w/ Sticky gel
Front brake Shimano Dura-Ace 9110F direct mount
Rear brake Shimano Dura-Ace 9110RS direct mount
Front derailleur Shimano Dura-Ace Di2 9150, braze-on
Rear derailleur Shimano Dura-Ace Di2 9150, 11-speed
Shift levers Shimano Dura-Ace Di2 9150
Cassette Shimano Dura-Ace 9100, 11-speed, 11-30t
Chain Shimano Dura-Ace,11-speed
Crankset S-Works carbon fiber
Chainrings 52/36T
Bottom bracket OSBB, CeramicSpeed bearings
Front wheel Roval CLX 50, Win Tunnel Engineered, carbon rim, 50mm depth, Roval AF1 Hub, CeramicSpeed bearings,16h
Rear wheel Roval CLX 50, Win Tunnel Engineered, carbon rim, 50mm depth, Roval AF1 Hub, CeramicSpeed bearings, 21h
Front tyre Turbo Cotton, 700x26mm, 320 TPI
Rear tyre Turbo Cotton, 700x26mm, 320 TPI
Seatpost S-Works FACT Carbon Tarmac seatpost, 20mm offset
Saddle Oura Pro 155


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