Felt Bicycles Technology

THE CHALLENGE. equilink suspension
When Felt first set out to develop our new full suspension design platform, we were more than aware of the challenges that lay ahead. After all, fresh concepts are difficult to prove, very expensive to develop, and existing patents are fiercely protected. We knew no one would take us seriously if we just licensed existing technology, so a me-too product was never an option.

We started with a clean sheet of paper.

In order to succeed, we knew we would need to design a package comprised of a very diverse blend of attributes. Rider’s expectations can seem contradicting at times: They want more travel and greater durability, yet they want lighter weight. They want their suspension to remain active at all times, but they will not sacrifice any measure of efficiency. They want it to be predictable and consistent throughout the range of travel, and regardless of gear selection. They want no bob, no pedal kickback, easy set-up, and maximum tune-ability. And of course, riders want all of these qualities to be wrapped up in a design that is not only easy to understand, but simple to service. Needless to say, our engineering team had their work cut out for them.

THE GOALS

While there is no shortage of suspension concepts on the market meeting some of (and a varied mix of) these demands, we could not find a single system that met them all. Our goal was to develop the complete full-suspension Experience for our customers. This Experience for the rider would be all-inclusive; designed around achieving a perfect balance of all of the qualities they dream for their bikes to possess. In short time, we realized that, from the long list of rider demands, all of the qualities essentially pointed to the same two basic elements:

FAST AND SIMPLE.

These two elements would become the primary driving force for the Experience that we would one day deliver. l Additionally, we knew we needed a suspension technology that could be applied to any type of bicycle; from XC short travel racers to Endurance and All-Mountain models, to longer-travel Freeride and DH machines. Luckily, we had no shortage of desire to make it happen.

THE EQUILINK SOLUTION.

After nearly three years of extensive testing, evaluation, and R&D, a revolutionary and patented suspension technology named Equilink was born. The magic of the system lies within the red Equillink positioned vertically behind the seat tube. This innovative yet mechanically simple link counteracts weight transfer on its own, allowing the drivetrain to do only what it was meant to do; propel the rider forward. By equalizing the forces of acceleration and rider input, the suspension remains open and active while moving you forward with the greatest efficiency.

FAST

Unrivaled efficiency. No bob. No pedal kickback. Always predictable and consistent. Active in and out of the saddle. Sensitive to the smallest of bumps.

SIMPLE

Tune-ability is an option – not a requirement. No hard-to-find sweet spot. Whether it’s initial set-up, on the trail adjustment, pro-tuning or servicing…simplicity is what Equilink delivers.

Finally, a single suspension design platform that possesses it all, and one that can be applied to any riding discipline.

Equilink technology was first employed one year ago on our Virtue series of high-performance Endurance Race/Trail models delivering over 5” (130mm) of amazingly fluid and ultra-efficient travel. For 2008 we are excited to have expanded the technology into 145mm travel Compulsion (Aggressive Trail) and 165mm travel Redemption (Aggressive All-Mountain) categories.

Note the red Equilink positioned behind the seat tube. This equalizing link counteracts weight transfer on its own, so that the drivetrain doesn’t have to.

As you pedal, the red link automatically pulls down on the upper horizontal link, which instantly negates and equalizes weight transfer. The harder you pedal (the more weight transfer you initiate), the Equilink simply mirrors the effort, keeping a constant state of equalization.

By allowing the drivetrain to do what is was meant to do (move you forward), we are able to maximize pedaling efficiency while allowing the suspension to remain equalized, and ultra-compliant as it moves freely over even the smallest bumps.

EQUILINK = FAST [top]

1: LIGHTWEIGHT

Equilink was designed to be virtually limitless in regards to frame design. You will see no tubing interrupted with pivots (which need to be beefed up to handle the loads), no need for massive gusseting, no need for oversized or complicated tubing formations. The Equilink system is rather compact in itself, enabling the frame to utilize very simple, lightweight, traditional, no-nonsense tubing, as exemplified on our Virtue series of endurance race models.

2 : COMFORT

A comfortable rider can focus all his/her energy on pedaling, rather than the distraction of constantly shifting/adjusting the body position due to terrain input.

3 : ENDURANCE

Over time, efficient shock absorption conserves energy, increasing power output.

EQUILINK = SIMPLE [top]

1 : SET-UP

At Felt we believe that riders should be able to set up their bike quickly, easily, as they like, and without a narrow window for error. Many suspension bikes today require complicated, time-consuming,
and very specific setup procedures. Among them are a very precise air pressure/sag setting, limited damping settings (e.g. firm, firmer or lockout), inertia valve settings, etc. We believe a rider should not suffer a poor ride or a bad day just because he/she was off by a few PSI or a small click of a dial.

2 : NO SWEET SPOT

Some suspension bikes are known for their "sweet spot" when it comes to how the suspension performs under certain conditions and certain settings. Obviously, finding and adjusting your bike to find this sweet spot can be challenging and time-consuming. How nice would it be to have a bike with a sweet spot
throughout the entire range of travel? So, if you happen to be "off" by a few PSI, you don’t end up with bobbing or pedal kickback; you just end up with a little softer or firmer ride.

3 : TUNE-ABILITY

We believe that tune-ability should be an option - not a requirement. If a rider wants to try out a platform valve shock, it’s no problem. If someone feels they just have to have a lockout, feel free. While the Equilink system was designed to offer the utmost in efficiency without these types of shocks, we recognize that they can indeed change the ride characteristics and that some riders may like to experiment with what these types of shocks can offer.

4 : NO SPECIAL SHOCK

Some suspension bikes are designed to be dependent on one type of shock, made by one shock maker, tailored to a specific rider weight/size. This usually comes at a high price and inconvenience,
assuming you are able to get your hands on one in your area. The Equilink system, on the other hand, was designed to accept any brand of shock, around conventional shock
lengths, without requiring specific internal factory settings.

WHEN IT COMES TO INITIAL SET-UP, ON THE TRAIL ADJUSTMENT, PRO-TUNING, AND SERVICING, SIMPLICITY WAS ALWAYS AN ABSOLUTE REQUIREMENT FOR THE EQUILINK SYSTEM.

EQUILINK = EFFICIENT SUSPENSION [top]

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1 : NO BOB

Equilink is the first bicycle suspension system to effectively eliminate the use of the drivetrain as the primary mode of counteracting weight transfer (the cause of bobbing). Equilink was specifically designed to neutralize the effects of weight transfer without the direct use of direct chain force, achieving a perfect state of suspension "equalization". By keeping the drivetrain independent of the suspension, it is allowed to perform the job it was solely intended: to propel the bicycle and rider forward.

2 : PREDICTABLE & CONSISTENT

On most bikes, the level of anti-squat (or anti-bob) can vary greatly, depending on which gear combination you are in (because the amount of leverage the chain has over the pivot changes along with the gear selection). For example, the large chainring/small cog will produce very different results than the small chainring/large cog combination (and one can imagine the many possibilities in between). The typical result is suspension that is inconsistent and unpredictable. With the Felt system, the red Equilink is employed to do the work normally carried out by the chain itself, resulting in stable and consistent antibob characteristics in any gear combination, at any speed.

3 : NO PEDAL KICKBACK

Near vertical axle path ensures smooth pedaling circles regardless of gear selection and terrain input.

ALL THREE OF THESE FEATURES CONTRIBUTE TO THE AMAZING EFFICIENCY OF THE EQUILINK SYSTEM.

EQUILINK = ACTIVE SUSPENSION [top]
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1 : IN/OUT OF THE SADDLE

Equilink is not prone to shifts in spring rate, whether the rider is seated or standing. Equilink remains active when sprinting out of the saddle, hanging over the back on a downhill, or seated on a long, slow uphill grind.

2 : SMALL BUMP SENSITIVITY

The surge in popularity of platform damping or brain shocks reflects the amount of inefficient suspension designs on the market today, especially when it comes to small bump sensitivity. Platform shocks are often employed to mask inherent design inefficiencies. The problem is: When you over-damp a shock to hide rider-induced shock movement, you can also stop the shock from reacting to smaller terraininduced movement. At Felt, we believe that suspension should be active all the time, to pick up the small as much as the big, enhancing comfort, as well as traction. We believe platform valving should be used ONLY to smooth out unwanted shock movement due to inconsistent (jerky) pedaling - not to counteract bob caused by rider weight transfer.

A TRULY ACTIVE SUSPENSION DESIGN IS ONE THAT WORKS EQUALLY IN OR OUT OF THE SADDLE, POINTED UP OR POINTED DOWN, AND SENSITIVE TO THE TINY STUFF AS MUCH AS THE BIGGER HITS. [top]