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Diamondback recently released a teaser video featuring an all-new triathlon/time-trial bicycle, the Serios. The release of this bike is anticipated to coincide with Ironman World Championship race week. While Diamondback has not released much in the way of details on the new bike, we can gather quite a bit of intel by studying the video which announced its release.
Up front we see an hourglass shaped head tube provide the frame’s leading edge. This helps to optimize aerodynamics while still providing the front-end stiffness one would hope for during out-of-saddle efforts. Diamondback did choose to forgo any sort of integrated front brake, an interesting move given how ubiquitous they are on the bikes of their competition. An integrated stem rests in line with the top tube in when used without any spacers, in its lowest position, which is a popular trend in the industry at the moment. More uniquely, the Serios appears to have proprietary spacers that can be used to adjust stem height while minimizing the aerodynamic impact of doing so. A top tube that tapers as it moves away from the head tube also hints at better front-end stiffness while aiding aerodynamics, by removing material where it is not needed.
The Serios incorporates selective use of truncated airfoil shapes, most notably on the seat tube above the junction of the seat stays. The seat stays themselves move toward the main frame at a sharp angle, lowering their position presumably in an attempt to improve aerodynamics. While the stays are curved, we are unsure at the moment if this is an aesthetic move or if there might be a claimed benefit to the unique shape.
Questions of fit are often quite difficult to speculate on without seeing actual frame measurements, but we can make a few educated guesses based on what we’ve seen in the video. The seat post on the Serios appears to be a highly adjustable design. While this bike’s release coincides quite obviously with Kona, the teaser video features former U.S. Time Trial national champion Tom Zirbel, so the bike will obviously serve double duty as both a triathlon and time-trial rig, meaning it will need to serve two camps of riders: time trialists who require a more slack seat tube angle, and triathletes who have historically preferred and benefited from a much steeper seat tube angle. Expect effective seat tube angles of 72–80 degrees. The height of the head tube also looks promising for triathletes, though again this is based only on the images in the teaser video. Tom Zirbel is relatively tall, and so what appears to be a tallish head tube on his large frame size in the video might not necessarily translate to tall head tubes throughout the size run. What is more clear from the video are the previously mentioned uniquely shaped steerer spacers, meaning Diamondback was intent on allowing for some amount of front-end adjustment. It appears that Zirbel is using between 3–4cm of these spacers.
The Serios also displays clean brake and shift cable management, with cables entering the top tube just rear of the stem before heading to the rear triangle of the frame. Another welcome feature for triathletes is hardware on the top tube to mount nutrition systems, and water bottle cage mounts on the frame.
While there is still quite a bit to be learned as more details of the Serios are released, it is very good to see another brand enter the triathlon market with a bike that the company obviously put a lot of work into. Just based on some of the features we can see in the teaser video, the Serios will likely be a bike that many triathletes might consider when they are next in the market for a new rig.