FourBy4 Suspension

FourBy4 Suspension

Our Fourby4 suspension platform is the cornerstone of Knolly Bikes. When our CEO and Chief Engineer, Noel Buckley, set out to design his first bike (the V-Tach), he started with a suspension philosophy and a list of ride characteristics that were important to him. He designed his suspension technology first, prioritizing traction, ride balance and suspension performance while braking. He rode the first prototype and knew he had a winning design, so he applied for patents and Knolly Bikes was born.

Inspired by Formula One auto racing strut-style suspension, Knolly’s patented Fourby4 suspension provides freedom in design and execution that no other design in the industry can tout. This freedom means that we can design each model from the ground up and manipulate wheel path and shock progression completely independently. It allows each model to have suspension rate curves that are generally linear to progressive, which is important because it means your shock doesn’t have to ‘save the day’ by providing lots of bottoming resistance, as it would on a bike with a falling rate curve. It keeps your shock from being overworked and overheating on long downhills, which can affect shock performance. This also helps maintain normal shock service intervals. Each of our suspension bikes have rate curves and leverage ratios that are implemented for a certain type of riding (trail, AM, DH), while all models share some fundamental ride characteristics:

  • Pedaling Efficiency
  • Traction (inversely proportional to Pedaling Efficiency)
  • Rear Brake Interaction preloading the Rear Shock (i.e. negatively affecting both traction and suppleness)
  • Rear Shock Progression (often called “Leverage Curve”)


No suspension design in the world can fully optimize all of these forces but more sophisticated suspension designs can do a better job than lesser designs. For example, well engineered multi-link bikes can achieve a higher level of pedaling performance for a given amount of traction. They can also have the ability to tune rear shock progression and can do a significantly better job isolating rear braking forces from the rest of the suspension. However, even within the complicated world of multi-link bikes, there are differences and not all designs are created (or implemented) equally. A really good multi-link bike can have subtle differences that allow the designers to fine tune control of suspension forces to an even higher level and they can also focus on one particular area (i.e. pedaling efficiency or shock progression).

Although each of these designs is still constrained in that they have to work with the four fundamental forces managed by a mountain bikes’ suspension system. Our Fourby4 linkage system takes this to another level because our patented design allows us to separate the forces and to fully optimize them to suit each of our models intended purpose. This is why our bikes have an unrivaled reputation for suppleness, plushness and bottom out control. Fourby4 separates rear shock progression so that we can tune it effectively without affecting the other three performance characteristics. This also means that we can tune pedaling efficiency, rear wheel traction and rear brake neutrality without having to consider rear shock control. The engineering term is 'orthogonality' and it means that things (forces for example, or more accurately vectors) act at a right-angle to one another and therefore don’t affect one another.

Traction

Our Fourby4 suspension is a fully active design that is all about traction. There is no complicated pedaling platform designed mechanically into our frames, which means there’s nothing getting in the way of you receiving every ounce of traction on the trail.

Pedaling

Many bikes feature suspension designs that require a certain amount of chain torque in order to pedal smoothly. The problem with this philosophy is that you are never able to turn this ‘feature’ OFF in order to enjoy fully active travel and optimal traction. Knolly’s Fourby4 suspension pedals well in all iterations, without the need for complicated linkage tricks. Our active design provides a baseline for smooth pedaling characteristics, which can then be enhanced by any number of suspension shocks on today’s market. These shocks can provide a lockout or low-speed compression adjustment, which gives the rider total control over how the bike feels while climbing and descending.

Braking

Braking forces can impact how your bike tracks and finds traction. Fourby4 is a fully active design under braking forces, which is accomplished by proper pivot location. There is no brake induced suspension lockout and no brake jack, our suspension performance is smooth and reliable no matter how hard you’re gripping your brake levers.

Rear Shock Control

When we talk about maximizing Rear Shock Control, we can tweak this characteristic between models in a very predictable way that allows our bigger bikes to have incredible suppleness, plushness and bottom out control while our lighter duty models focus more on shock support when climbing while still maintaining adequate mid-stroke and end of stroke composure. We can easily accommodate the more progressive air springs of Trail inline shocks or more linear spring rates of coil and high volume air Enduro and DH shocks.

At its heart, Fourby4 allows for the separation of competing suspension forces and it is the only suspension system in the world that can do this. Simply put, conventional single pivot or multi-link (four bar, short link, etc…) bikes make more compromises and they need to trade off performance in one area to get more performance in other areas. Knolly does not.