Specialized’s approach to the Tarmac SL6 design process was somewhat conflicted: it wanted a lighter bike that was stiffer and more comfortable, but it didn’t want to change the handling or ride position.
So the chassis retains parallel, steep 73.5-degree angles and a low stack (591mm on my 58cm test bike), keeps the long reach (402mm), and the wheelbase creeps up to just 2mm over a metre. In fact, the only geometry change is dropping the bottom bracket height by 3mm (the SL6 is designed around 25mm tyres on wide rims, the SL5 around 23s on skinny rims).
- The Specialized Tarmac SL6 Comp Disc is one of our Bike of the Year bikes for 2019. To read reviews of the other contenders and the categories tested across road, mountain and women’s bikes, visit our Bike of the Year hub.
On the road, the SL6 has all of the familiar Tarmac traits: huge pick-up from hard pedal efforts and neck-snappingly fast reactions to steering inputs. This all adds up to an addictively rapid, sharp and snappy bike. Yet, while the Tarmac is every inch a racer’s tool the SL6 has evolved.
Instead of the top-of-the-line 12r carbon you’ll find on the S-Works and Sagan edition bikes, the Comp has a 9r carbon frame and a 10r carbon fork, which adds 100g or so to the frame, and a smattering to the fork.
Component wise Specialized has compiled a decent mix. It’s good to see a complete Shimano Ultegra groupset (including Ultegra cassette and Icetech rotors) and the 52/36 and 11-30 cassette gearing which favours speed merchants. The wide cassette gives a great bailout climbing ratio of 36/30, which should see even the most modest of climbers to the summit.
In recent years, Specialized has relied more on its in-house wheel brand Roval, so it was a bit of a surprise to find DT Swiss’s competent, if unremarkable, R470DB hoops here.
The rim is a great shape (23mm deep, 20mm internal), reasonably light at 450g and tubeless compatible too. Those rims are built on Axis (Specialized hubs with DT internals) with a competitive weight at around 1,500g a pair.
The Turbo tyres are excellent with supple casing and impressive grip in the wet. You don’t often see 26c tyres, but mounted these push out closer to a 28 than a 25 and I certainly appreciated the smooth roll afforded by the increase in volume.
Specialized does contact points well. While the alloy bar is a little harder edged than I’d have liked, it’s wrapped in tacky-to-the-touch and plush padded Roubaix tape, and feels comfortable.
The plump, gel-padded Toupé saddle isn’t my favourite in the BG range, but it’s comfortable and inoffensive, which is about as much as you can expect from a standard-issue seat.
Aside from the familiar handling, what does impress is just how well the SL6 copes with poor road surfaces. Aided by those 26mm Turbo tyres, it smooths out gritty and rough-edged tarmac. The back-end’s dropped stays and premium S-Works carbon seatpost meld to make a beautifully compliant ride. The front end, with its all-alloy cockpit does reach its comfort threshold faster, but I’d never describe riding the Tarmac as harsh or hard.
The quality ride and quick handling combine to deliver a bike that feels superbly balanced. Hit a lump or a pothole and the chassis settles quickly after the initial whump. It seems strange to describe a fast-handling racing machine as balanced or stable, but that’s just what the SL6 is.
Throw it into a descent and the frame and fork’s compliant yet lively feel delivers confidence in spades. I felt absolutely at home pushing the Tarmac fast and deep into corners, relying on a combination of the frame’s agility and the superb Icetech rotor-equipped Ultegra brakes, with a big 160mm rotor up front to keep a lid on any unwanted noise.
Overall, the Tarmac Comp stacks up as a great bike. At £2,900 / $3,500 / $4,300 it’s about on the money for an Ultegra-equipped machine. For a similar outlay, you can find a few bikes out there with a higher value parts, such as the Giant TCR Advanced Pro 1 Disc, Ribble Endurance SL, Fuji SL 2.3, but not many can match the Tarmac’s combination of ride quality and handling prowess.
If you’re a fan of previous Tarmacs, the SL6 won’t disappoint, and if you’ve never tried a Tarmac before maybe it’s time to see what one of the winningest bikes ever feels like.
Specialized Tarmac SL6 Comp Disc specification
- Sizes (*tested): 49, 52, 54, 56, 58*, 61cm
- Weight: 8.33kg
- Frame: SL6 Fact 9r carbon
- Fork: Fact 10r carbon
- Chainset: Shimano Ultegra, 52/36
- Cassette: Shimano Ultegra, 11-30
- Shifter: Shimano Ultegra
- Derailleurs: Shimano Ultegra
- Brakes: Shimano Ultegra
- Wheels: DT Swiss R470 disc
- Tyres: Specialized Turbo Pro Gripton 26c
- Stem: Specialized 3D forged alloy
- Bar: Specialized shallow drop alloy
- Seatpost: S-Works FACT carbon
- Saddle: BG Toupé Comp gel
Specialized Tarmac SL6 Comp Disc geometry
- Seat angle: 73.5 degrees
- Head angle: 73.5 degrees
- Chainstay: 40.7cm
- Seat tube: 54cm
- Top tube: 58.1cm
- Head tube: 19cm
- Fork offset: 4.4cm
- Trail: 5.5cm
- Bottom bracket drop: 7.2cm
- Bottom bracket height: 26.8cm
- Wheelbase: 1,002mm
- Stack: 59.1cm
- Reach: 40.2cm
- Price: £2,900 / $3,500 / AU$4,300