Originally posted Oct 4, 2018
It might come as a surprise, but when engineers first applied front suspension to a bicycle, widespread adoption of telescoping forks was not a foregone conclusion. Linkage front suspension systems have been applied to bicycles since the advent of mountain biking, and a number of such systems are still sold and work exceptionally well.
The number of linkage front suspension designs that have made their way to market - including Bridgestone, Lawwill, Look, Amp Research (developed by Horst Leitner, famed for Horst rear suspension), Girvin/Pro-Flex/Noleen (purchased by K2), Hurrycat, Parafork, Whyte (PRST-1 and PRST-4), German A, Lauf (they aren’t telescoping forks, so we’ll note them here), and more recently Scurra, Motion Ride, and Structure Cycleworks - demonstrates that enthusiasm for linkage front suspension is alive and well. Although widespread market adoption has eluded linkage systems until now, it has more to do with simplicity, aesthetics, and cost savings than outright performance.
That flexibility in thinking about how to make a bike move, how to orient frame members and package components - and about what standards to adopt, what sort of hardware to use, and what materials to use for the frame - has proven to be an advantage and a constant challenge.
A few decisions were straightforward. Enduro was our category because it’s how we ride local trails. Boost and 27.5” are standards that we don’t regret adopting. All bearings and components had to be standard bike fare that can be replaced at a local bike shop, even if the frame itself seems exotic. Basic geometry and fit had to be what riders expect, although we made a number of decisions to get ahead of trends and take best advantage of the stability-enhancing kinematics of our linkage chassis.
Other decisions have been more challenging. Where should the front shock be located? Should it be actuated directly or by link / rocker? How long should the front arms be? How much brake anti-dive is too much, negatively impacting bump compliance? How do we minimize stack (fork + travel + upper steering head) while keeping the entire system stiff and strong? How steep should the seat tube be, and should we prioritize actual or effective seat tube angle? How far should we go to keep mud and water out of bearings? (We went to extremes, with x-ring seals at each main pivot).
Drawings - from early sketches to recent eDrawings - illustrate how the design of the SCW1 evolved as decisions became firm. For example, packaging and actuating two shocks influences the shape of everything around them, as you can see here:
But form matters too. As much as we might like to think that we can fight human nature, beauty gets attention, and one reason for bike market rejection of past front linkage suspension systems has been that no matter how well they function, they haven’t always been pleasing to the eye.
Aesthetically, not everyone loves our work, although it’s gratifying that many do. Some see a leaping gazelle or cheetah; others a praying mantis.
However, there has not been a design revolution that addresses the limitations of telescoping forks while offering the kind of massive improvement in performance that will assure adoption by hardcore enthusiasts everywhere.