2023 SPECIALIZED DIVERGE STR REVIEW: ABSURDLY COMFY, BUT ALSO HEAVY AND PRICEY

30 mm of rear suspension travel, 20 mm of front travel, and clearance for 700x47 mm knobbies is a formula for a good time on rough terrain.

Specialized engineers and designers will cringe at my description of the new rear Future Shock system as just a super long seatpost, but that’s essentially what it is. 

Conventional bikes usually use a telescoping seatpost clamped somewhere around the seat cluster. Some frame flex happens below that point, but by and large, all the action happens above the clamp. The current Specialized Diverge and Roubaix (along with other bikes using similar concepts like the Canyon Aeroad and Endurace) already move the seatpost clamp a few centimeters further down, but the new Diverge STR takes the idea to the extreme. 

The rear Future Shock system uses a conventional 27.2 mm-diameter seatpost, but it’s clamped inside something Specialized calls a “framepost”. That framepost runs inside the length of the seat tube, and it’s anchored just above the bottom bracket shell. The seat tube is flared such that the framepost (and the seatpost attached to it) is free to flex fore and aft inside of it to provide the desired back-and-down travel path. 

Having that long of a seatpost is great for flex, but without something to control the motion, you’d basically be riding a diving board. As such, there’s a hydraulic damper attached to the top of the framepost, hidden inside the top tube and connected together with what Specialized calls an aluminum “tendon”. 

According to Specialized, the rear Future Shock system provides up to 30 mm of travel (potentially more if you really, really hit something massive), and the back-and-down direction of travel is aligned with how the bump forces are coming up through the rear wheel. Nine different frameposts – each with a distinct spring rate – are available to help tune the feel for riders weighing anywhere from 45-122 kg (100-270 lb). Each of those framesets is also built with a directional layup, so rotating it 90° in the frame provides yet another slight spring rate variation, making for 18 different spring rates in total. 

Interestingly, because the framepost is designed to handle the bulk of the comfort duties, Specialized doesn’t encourage the use of a flexible seatpost since there would then be too much uncontrolled movement. In fact, none of the new Diverge STR models feature the comfy-riding Roval Terra carbon post stock, but the upside of that is any 27.2 mm-diameter post will theoretically provide the same level of comfort. Notably, that includes dropper seatposts, which typically serve up a bone-rattling ride quality as compared to a good ride-tuned carbon post.

The damper inside the top tube is the same across the board. Specialized says the same base tune works for everyone, but rebound speed is adjustable with an Allen key, and compression speed can be set on-the-fly with a little lever in three steps: fully open, intermediate, and locked. 

All in, Specialized says the rear Future Shock system adds about 400 g (0.88 lb) as compared to a similar non-STR Diverge frame. In other words, the rear Future Shock story certainly isn’t about making things lighter, but Specialized insists that the improvement in ride comfort is more than worth the extra weight.

“On smooth surfaces, rear Future Shock remains still, only reacting to surface bumps to ensure a smoother ride, while eliminating any pedal induced bobbing for optimum efficiency and compliance without compromise,” reads the marketing spiel. “On rough surfaces, the Diverge STR shows much more compliance, or down and back saddle movement, than the already industry-leading Diverge with a Roval Terra post. The result? A reduction in vibration at the saddle of more than 20% for a much smoother ride.

“Bottom line? Diverge STR is a smoother ride on both smooth and rough gravel, while ensuring pedaling efficiency, optimum control, and total confidence thanks to suspending the rider, not the wheel.”

The rest of the Diverge STR

Aside from that main development, the rest of the new Diverge STR isn’t all that different from the current Diverge.

Sitting atop the steerer tube is the same Future Shock 2.0 suspension cartridge that Specialized updated in 2019 on the Roubaix, and the same 20 mm of available travel. Frame geometry is nearly identical across each of the six available sizes, with the primary exceptions being 5 mm of additional bottom bracket drop and 4 mm of extra chainstay length on the STR for even more stability. Although the measurements are almost the same, the new Diverge STR certainly looks more low-slung what with its skeletal seat cluster area and those GT Triple Triangle-like extended seatstays, which flow into the top tube well forward of the seat tube. 

There’s a bit of aero shaping evident here (particularly in the down tube), but Specialized isn’t touting the Diverge STR as being particularly efficient at cutting through the air. Instead, there’s more focus on capability. Specialized says the new Diverge STR is officially approved for tires up to 700×47 mm (and will even clear “most 50c tires”), and while a 27.5×2.1″ setup is “totally fine” in terms of bottom bracket drop, it likely isn’t necessary since there’s so much clearance with the larger 700c wheels. 700×42 mm tires will come stock, and between that tire specification and the extra suspension out back, Specialized is clearly intending the Diverge STR to be the most off-road-oriented of the Diverge family.

Mounts are about the same as the standard Diverge with three bottle mounts on the main triangle (one underneath the down tube), a top tube feed bag mount, and mounts on each fork leg. A thick molded rubber guard protects the lower third of the down tube (together with a full-length strip of clear vinyl tape), while the chainstay protector is another big chunk of molded rubber with raised bumps to quell chain slap noise. Technically speaking, there are mounts for a front fender should you want one, although Specialized apparently really intends those holes to be used with a lowrider rack should you decide to do some bikepacking. You’ll have to get creative out back, however, as there are no fender or rack mounts back there.

As on the regular Diverge, the STR’s down tube doubles as a surprisingly spacious (and almost weatherproof) storage container. Underneath the quick-release panel hiding underneath the down tube bottle cage is enough room for a flat kit, a light jacket, and some snacks. Inside, the base of the frame is walled off so smaller items don’t end up rubbing on the bottom bracket spindle.

Specialized has thankfully passed on the fully internal cable routing trend, instead sticking with the more traditional (and vastly more practical) semi-internal setup with lines running only through the main frame. Two entry points are located on the non-driveside of the head tube for the rear brake line and optional dropper seatpost, and both paths are fully guided end-to-end inside the down tube for easy plug-and-play servicing. 

The new Diverge STR is only compatible with wireless electronic drivetrains, however, as there’s no provision up front to feed a previous-generation Shimano Di2 wire into the frame (a port is provided at the rear driveside dropout). 

Claimed frame weight for the new Diverge STR frame is 1,100 g for a 56 cm size without the rear Future Shock bits, or about 1,400 g all-in.

Models, pricing, and availability – and how other Diverges are affected

Specialized is offering just three Diverge STR models, all built around identical FACT 11r (Specialized-speak for its premium blend of carbon fiber) framesets, and all outfitted with SRAM “mullet” 1×12 wireless electronic groupsets and 42 mm-wide Specialized Tracer Pro tubeless tires. All of the new bikes will supposedly be available right away – at least in limited quantities, and primarily in US and EU markets. 

Brace yourself for the retail prices, as all of the Diverge STR models are very expensive, too – roughly US$1,000 more than a similar non-STR Diverge.

The top-end S-Works Diverge STR features a SRAM Red eTap/XX1 Eagle AXS 1×12 wireless electronic groupset, a Quarq spider-based power meter, Roval Terra CLX carbon clinchers, a Roval Terra carbon handlebar, and an S-Works carbon seatpost for US$14,000 / £13,000 / €15,000. Actual weight for a 56 cm sample was 8.62 kg (19.00 lb) without pedals or accessories.

The mid-range Diverge STR Pro goes with a SRAM Force eTap/X01 Eagle AXS 1×12 wireless electronic groupset (without power meter), Roval Terra CL carbon clinchers, and the same bar and seatpost for US$9,500 / £9,000 / €9,500. Actual weight for a 54 cm sample was 9.04 kg (19.93 lb) without pedals or accessories. 

Finally, there’s the not-really-entry-level Diverge STR Expert with a SRAM Rival eTap/GX Eagle AXS 1×12 wireless electronic groupset, Roval Terra C carbon clinchers, the same S-Works carbon seatpost, but an aluminum Hover handlebar for US$7,500 / £7,500 / €7,500. Actual weight for a 54 cm sample was 9.67 kg (21.32 lb).

Australia will only get the Diverge STR Expert (AU$10,500), although a bare frameset will also be offered there and in the US for US$6,000 / AU$8,500.

The introduction of the Diverge STR has some big impacts on the rest of the Diverge range, too. According to Specialized road and gravel category leader Stewart Thompson, the new STR is, “the ultimate expression of the Diverge concept, and the pinnacle of the Diverge line.” But that also means riders keen on a premium-level, non-STR Diverge had better start looking for MY2022 closeouts.

Specialized will phase out the S-Works and Pro levels of the standard Diverge completely, leaving the Diverge Expert and Comp as the top-level non-STR offering with its lower-end FACT 9r carbon construction. There will also be a Diverge Carbon Sport model that’s built with a FACT 8r carbon blend, and does without the handy down tube storage hatch. 

Rounding out the Diverge frame range moving forward are two aluminum models: the Diverge E5 Future Shock at the Comp level, and the Future Shock-free Diverge E5 at the Comp and base levels. 

Like it or not, this is where Diverge is going.