Polygon XQUARONE EX9 First Look - Mountain Biking Australia
Polygon bikes has just launched the XQUARONE; a new 27.5 wheeled bike that features an all-new suspension system. Suspension designs have become quite refined in recent years and most fall under a few simple categories; single pivot, Horst Link, short-link four-bar and so on. The actual pivot placement will vary, and this has a big impact on how each system performs, but on the whole these designs follow similar lines.
The suspension system found on the new Polygon Square One was designed by Darrell Voss; an industry veteran who has worked for brands such as Klein, Kool Stop, Trek and SR Suntour. Called ‘R3act’ it uses a one-piece elevated carbon fibre swingarm, but the unique bit lies in the links that connect the swingarm to the frame.
It uses a relatively traditional looking short upper link but the lower link incorporates a sliding member that’s not unlike the stanchion tube on a fork. It slides and extends as the swingarm moves through its travel. This sliding link is hidden inside the chunky carbon swingarm and the two links control the axle path. In this regard it’s like a short-link four-bar but an extremely unique take on one.
The end result is said to produce excellent anti-squat characteristics for efficient pedalling, so much so that Polygon runs a custom tuned version of the Fox X2 shock with 60% less damping. Darrell Voss believes that added damping force isn’t needed with the R3act system and the suspension kinematics delivers efficient pedalling, even with 180mm of rear wheel travel. We’re certainly keen to get one on test to see how this plays out.
While the suspension undoubtedly grabs your attention, the geometry has also undergone quite a transformation. With a 445.8mm reach on a medium, 461.8mm on a large and a 471.4mm on an extra-large, the reach is substantially longer than the previous offerings from Polygon. It’s more in keeping with current trends and will allow the used of a short stem without feeling cramped.
The 66-degree head angle isn’t really slack for a 180mm travel bike but it’s a safe figure for a bike that’s designed to go uphill efficiently as well as descend. At the opposite end, the Square One runs super-short 425mm chainstays. While the seat angle appears to be very slack, the effective angle comes out at a moderate 73.5-degrees. So geometry-wise, it is very progressive although it’s worth noting there’s no small size in the lineup.
Aside from these figures, the XQUARONE will clear 2.6-inch wide tyres, the frame is all-carbon and the rear suspension is matched with a 180mm travel fork. We’ll see two models in Australia; the top-end EX9 and the EX8. The range-topping bike comes with SRAM Eagle XX1 and a whole lot of carbon bling; wheels, cranks and bars while the EX8 runs alloy rims with SRAM Eagle X01. Both models will come with Factory level Fox suspension at both ends.