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The New 2018 Tarmac Disc is Here (Sort Of)

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If you’ve read the pages of PELOTON before, you know we are fans of the Specialized Tarmac. When it was launched the 2015 Tarmac was simply the best all around bike we had ever ridden. We rode the rim brake 2018 Tarmac at the launch event in June and our first impressions were very good, but since then, the bike has been delayed with very little availability. It’s been vaporware. Now Specialized has officially announced the disc version. We have images, and a promise that the wait is over. The 2018 Tarmac disc will be on bike shop floors any day.


The Tarmac remains Specialized’s ultimate expression of what a pure road bike should be. To improve on the 2015 bike Specialized created the most complex layup it has ever manufactured for the 2018 Tarmac Disc, more complex than the vaunted McLaren versions of previous Specialized bikes. Using its ‘Rider First’ engineering process 500 pieces of carbon, 200 more than the 2015 Tarmac used, dial in the same ride quality from the smallest size to the largest.

A look at the differences in the ‘Rider Tuned’ layups used to ensure the small sizes ride like the big sizes.

Aerodynamics are also improved, shaving 45seconds over 40kilometers, by dropping the seat stays, reshaping the fork blades, seat tube and down tube. Specialized claims the bike is as aerodynamic as the original Venge, yet retains the Tarmac feel. That’s something we will be paying close attention to during our testing when we get a bike in for long term review. Yes, we are hoping those long delays are truly over.

Same ride quality? We will find out.

While we don’t have stand alone disc frame weights, the Ultralight Tarmac rim frame is a claimed 733grams. The 2018 Tarmac Disc will add some grams to that and more evidence that frame weight has never been near the top of Specialized’s design brief. As absurd as it seems to say, when the Trek Émonda disc frame is under 700grams, the Tarmac disc, likely around 800grams, isn’t that light. Of course, package weight can be well under the UCI limit anyway, so it’s a bit of a moot point if the ride quality is there.

All new S-Works Tarmac builds will now come with Specialized’s new power meter, created in partnership with 4iiii’s. It’s the power meter Peter Sagan has relied on the past two seasons and will come in S-Works carbon crank flavors as well as Shimano alloy versions and single and dual side versions. Specialized claims its S-Works meter, at 440grams for a 172.5mm, is the lightest available and the most accurate. Specialized created a test protocol it believe makes its 1.5% +/- accuracy claim more believable than other manufacturers on the road, of course it’s consistency that really counts. The meter is both ANT+ and Bluetooth and can be set up and managed with a new Specialized Power App. One of the most appealing aspects of the S-Works meter for riders on either side of the bell jar is the range of sizes – 165mm to 180mm in 2.5mm increments.

The new S-Works Power Meter based on 4iiii’s technology.

A 2018 S-Works Tarmac disc frame set will set you back $4500, while a build with the new power meter, Dura-Ace Di2 9170, Roval CLX 50 wheels and S-Works carbon and alloy cockpit with an S-Works Toupé saddle will cost $11,000. There is a women’s version too, but it is the same frame with identical stack and reach numbers, just adjusted touch points like the Oura Pro saddle. The men’s bike is available in sizes 49 to 61, while the women’s builds come in 44 to 56mm sizes.

Look for an on test feature and long term review soon after of the new Specialized S-Works Tarmac disc. For more info head to