Specialized S-Works Tarmac SL8 Dura-Ace Di2 review

Specialized has officially unveiled the new Tarmac SL8 on men’s road race day at the 2023 World Championships.

The Tarmac SL8, said to be the fastest bike Specialized has ever made, is set to be ridden by select riders in the race, many of whom stand a chance of taking the top step on the podium this time round.

On the morning of the race, I got to take the new S-Works Tarmac SL8 for a spin in the rolling countryside around the host city of Glasgow.

Although 50km is only far enough to garner some very early impressions, the S-Works Tarmac SL8 certainly gives off the impression of a serenely quick, highly polished all-round race bike.

Considering the level of finesse (and success) the old Tarmac SL7 had achieved, this hardly comes as a surprise, but given time the SL8 might well prove to be the next standard-setter for the all-in-one race bike genre.

Specialized S-Works Tarmac SL8 first impressions

Given the new bike was subject to a number of leaks before the launch, the shape of the new Tarmac SL8 came as little surprise when it was unveiled to the media.

In the flesh, the new elongated head tube doesn’t look as otherworldly as it did in those spy shots, partly because it’s been paired with the new Roval Rapide integrated cockpit.

In fact, it’s remarkably subtle. Once I’d clocked it and moved on, I didn’t find my eye drawn to it again.

The slimmed-down seat tube and seatpost is another obvious change, but one that other brands (Pinarello’s F-Series immediately springs to my mind) are already jumping on in the search for improved airflow.

The rest of the bike is said to have been developed using the Specialized Aethos as inspiration to improve the stiffness-to-weight ratio, compliance and overall ride quality.

I’m not in a position yet to draw any definitive conclusions on that, but aesthetically at least, the new Tarmac SL8 looks well-proportioned, and a considered evolution of the Tarmac SL7.

Specialized S-Works Tarmac SL8 first ride impressions

My first taste of the Tarmac SL8 was a rolling 50km route in the countryside surrounding Glasgow.

Set up to my bike-fit specifications, I had an S-Works Tarmac SL8 complete in Shimano Dura-Ace Di2 R9200 trim, with Roval Rapide CLX II wheels.

The only switch to note is my choice of a Specialized S-Works Power Mirror saddle (bikes will come shipped as standard with a Romin Mirror perch), which Specialized says individual dealers can also make at their discretion.

Straight away, though, the bike felt easy to ride, well balanced and fundamentally quick.

That shouldn’t come as a shock to anyone familiar with the S-Works Tarmac SL7, given the geometry has remained purposefully unchanged.

I hadn't ridden the Tarmac SL7 before hopping on the SL8, but I’m assured the handling is identical to the old bike.

The front of the bike feels sharp and tactile without being overly sensitive – I found myself able to throw it from side to side out of the saddle with immediate confidence it wouldn’t dart too sharply (as I felt with the Orbea Orca OMX).

This confidence then fed my inclination to really put the hammer down and drive through the pedals on climbs and the rare bits of flat road I covered, as well as push the front of the bike into descents.

When I did, the S-Works Tarmac SL8 felt taut and stiff, but surprisingly stable and smooth too.

I’d have preferred to use 28c tyres (instead of the 26c S-Works Turbo 2BR rubber I’m told all S-Works bikes will be supplied with by default) for some more gains in comfort and ride stability on the Glaswegian roads. However, it’s a niggle I’d hope a dealer would be able to assist you with.

In any case, whether riding uphill, down dale or on flat roads, the sense of speed (and the ease with which it's delivered) is palpable.

Specialized S-Works Tarmac SL8 initial verdict

Just over 90 minutes of riding time is hardly enough to draw a definitive conclusion about the new S-Works Tarmac SL8.

That said, the early signs are Specialized has successfully buffed the already-polished Tarmac SL7 into an almost blinding shine.

It carries very few surprises, which is perhaps its greatest appeal. The recipe of the Tarmac SL7 – already so highly rated – didn’t need completely rewriting.

While this leaves open questions over whether a Tarmac SL7 (or even an SL6) owner should bite the bullet and upgrade their bike, the new Tarmac SL8 would appear to set a compelling standard for the all-in-one race bike genre.