Trifecta - The science behind the witchcraft | 08.02.22

High Pivot. Rate Control Linkage. Idler Position. Read on for the lowdown of what they are and how they combine to create the basis of the incredible ride feel on the Druid & Dreadnought from Forbidden Bikes

High Pivot

The first thing you can't help but notice when you see a forbidden for the first time is the high pivot and the way the chain seems to have found the long way between the cassette and cranks. What's going on there!?

Keep an eye on the rear axle as the Forbidden bikes move through their travel and suddenly the penny drops... the axle moves backwards throughout its whole path.

Have a look at any other suspension platform and that's not the case - sure, the axle moves up - but also forward, meaning the wheel is forced 'through' whatever its just hit, rather than just getting out of the way.

Getting that wheel out of the way means a composed and predictable ride - you're effectively lengthening the rear-center during a compression - literally, stabilizing the chassis when you need it the most.

As well as the rearward axle path, the high pivot setup has also allowed Forbidden to harness and tune their anti-rise figures, turning an often feared and misunderstood concept into a key contributor to your ride. Anti-rise describes the effect heavy braking has on your suspension platform. Traditionally considered a negative trait, modern trails and riding styles, both increasingly aggressive, have led to the concept being re-examined.

The realization that tuning suspension with one eye on anti-squat behaviours has allowed Forbidden to counter-act the fork dive that inevitably occurs when you drop the anchors on steep trails. In short - consistent chassis stability under heavy braking is how Forbidden describe the effect and that sounds like a pretty good thing to us!

Rate Control Linkage

The beating heart of Forbidden's Trifecta suspension system, the Rate Control Linkage, is used to manipulate the leverage rate as the suspension compresses.

Progression is the Holy Grail of mountain biking suspension these days. Modern riders, trails and Pinkbike commenters demand no less than miracles occur in the 60-something milimeters of a shocks stroke. Super plush, supple small bump sensitivity, somehow supportive and with lightening fast reflexes in the midstoke and seemingly bottomless when it gets near the knuckle...

Of course that's not all we ask of our suspension, there's also endless grip, enough 'pop' to make everything on a trail a take-off, the ability to take endless repeated hits on the gnarliest trails and not miss a beat when we're climbing over slippy rocks & roots...

The good news is Forbidden's engineers don't seem to have been phased by any of this. By employing relatively small links that see a dramatic change in velocity, they have been able to independently tune the critical stages of the shock’s compression, creating a leverage curve that's ticks every box on paper and on the trail. There's plenty of reviews online that agree with us when we say that they've nailed it.

Idler Pulley

The size and position of the idler pulley on Forbidden's bikes is critical, giving their bikes the efficient pedalling ability they’re known for. By carefully positioning the pulley, which is offset from the main pivot, Forbidden were able to fine-tune the anti-squat characteristics. Therefore both the Druid and Dreadnought exhibit what Forbidden have determined to be the ideal amount of anti-squat at sag to deliver a very stable pedalling response

Unlike traditional non-idler equipped designs Forbidden can achieve these levels of anti-squat with virtually no pedal kickback. This is great for flat pedal riders but it also means that the suspension remains fully active during pedalling efforts and in turn affords perfect traction on technical and punchy climbs.