Last month, we covered a Specialized Patent titled “Bicycle Frame with Angled Strut”. Today’s announcement of the 2023 Specialized Sirrus Carbon proves we were very much mistaken in thinking it could materialize as their next-gen spring classics road racing bike. Indeed, the angled strut frame finds its home on a model historically pitted as a comfort commuter, though with clearance for 700c x 42mm tires, the new Sirrus makes a compelling argument for its re-appropriation as a flat-bar gravel bike.
With the 2023 Sirrus Carbon, Specialized has looked to combine performance and comfort into a lightweight, versatile package. They even made it look rad, too. Pricing starts at $2,250 USD.
2023 Specialized Sirrus 6.0 Carbon and Sirrus X 5.0 Carbon
The 2023 Specialized Sirrus Carbon is a road- and gravel-worthy bicycle with a striking aesthetic thanks to what Specialized are referring to as the Compliance Junction. As the name suggests, it isn’t there to simply look cool; indeed, it is there to provide a little flex to the rear-end for improved forgiveness and comfort. We are told it does this without sacrificing performance and efficiency.
So, how much does it actually flex?
Well, an exact number of millimeters isn’t specified. However, if we look to the patent loosely pertaining to this frame design, we see that they tested the “Bicycle Frame with Angled Strut” to a vertical deflection of 7.9mm; that compares to the 2.9mm of vertical deflection they saw with the “conventional frame” that was tested alongside it. To learn more about the stiffness properties of the frame design in question, check out our coverage of the patent here.
There’s no getting around it; the 2023 Specialized Sirrus Carbon does look remarkably familiar. We simply can’t ignore the fact that a very similar frame design was very recently shown in the form of the Rondo Ruut V2 Carbon Gravel Bike. It too gets the “broken seat tube”, replaced by an angled strut that extends forward to meet the downtube, rather than the BB cluster. Specialized has pipped Rondo to the post, however, as the Ruut V2 won’t be available until later this year.
Where the Ruut V2 is a dedicated Gravel Bike with a drop-bar and (probably) clearance for higher volume tires, the Specialized Sirrus is more of an all-rounder, aimed at urban dwellers who want a bike that’s efficient enough for the daily commute, but not afraid to venture onto the gravel paths of the surrounding countryside.
The Compliance Junction isn’t the only source of vibration damping on this frame. Just like their dedicated Gravel Frame, the Diverge, the 2023 Sirrus Carbon also boasts the Future Shock, a unique suspension design housed underneath the stem that works to prevent the harsh frequencies caused by bumps in the road from reaching the rider’s hands. Positioned above the head tube is a concealed spring that moves in a vertical path. Unlike regular front suspension, the Future Shock does not cause any changes in frame geometry or wheelbase.
The 2023 Sirrus Carbon is well-equipped for longer rides with opportunity to mount three water bottles to the front
triangle polygon; one of the partial seat tube, a second on the downtube, and a third on the top-side of the top tube. The Sirrus is MIK compatible with mounting points for racks and fenders – in particular Specialized’s DRYTECH 42c fenders.
The Sirrus is available at two price points: $3,000 USD for the Sirrus 6.0, and $2,250 for the Sirrus X 5.0. They share the same carbon frame and fork, but differ on important spec like drivetrain, brakes and tires (specs below). Both are available in sizes XS-XXL, with the carbon layup of each frame tuned specifically such that the ride quality remains consistent no matter the size.
Reach stretches across a 350mm to 425mm range, with a consistent 440mm chainstay length on all frames. For a size guide on the Sirrus Carbon, head to the Specialized website.
2023 Sirrus Carbon Frame Details
- Frame Construction: Specialized FACT 9R Carbon, 12mm x 142mm thru-axle, Flat-Mount
- Fork: Specialized FACT 9R Carbon Monocoque, 12mm x 100mm thru-axle, Flat-Mount, Low Rider Mounts, Plug + Play Rack/ Fender Mounts
- Bottom Bracket: 68mm Threaded
- Tire Clearance: 700c x 42mm (w/o fenders); 700c x 38mm with fenders
- Seat Post: 27.2mm
Pricing & Availability
The 2023 Specialized Sirrus 6.0 retails at $3,000 USD, and is available in the Gloss Black / Pearl / Metallic White Silver / Black Reflective colorway only. The more affordable option is the Sirrus X 5.0 retailing at $2,250 USD, available in the Gloss White Mountains/ Gunmetal / Satin White Mtns Reflective colorway shown, or Satin Red Tint / Carbon / Black.