The Forbidden is a high single-pivot design, while the GT is a mid-pivot four-bar
In this, our second high-pivot idler bike test, we’ve upped the ante by increasing the travel. And by stepping into enduro territory – with the GT Force and Forbidden Dreadnought – we’re excited to see if idler designs make more sense in this arena. After all, enduro racing is much closer in nature to downhill than trail riding and idler bikes have definitely proved their worth on that stage. And while high-pivot idler bikes seem to be the current trend in bike design, no one can accuse Forbidden or GT of jumping on the idler bandwagon. Owen Pemberton, the man behind Forbidden, is no stranger to idler bikes, because before going his own way to start Forbidden Bikes he designed and developed the highpivot idler bikes for Norco. It’s a similar story at GT, only in reverse. Luis Arraiz designed and manufactured a four-bar idler bike under his K9 Industries brand as early as 2010. He’s now the current head of suspension development at GT, so it’s no coincidence that GT’S current idler design shares some of the same traits. Old dogs with old tricks? Possibly. But it’s more likely that both engineers were ahead of the curve and the rest of the industry is slowly catching up.
That’s not to imply that the GT Force and Forbidden Dreadnought are alike, though. Yes, they both employ idlers to help decouple chain forces for the suspension, especially under braking, but the Forbidden is a high single-pivot design, while the GT is a mid-pivot four-bar.
And while the last thing the bike industry needs is further fragmentation, it’s important to distinguish between both designs.
Due to the pivot height, the Forbidden has a more rearward axle path than the GT. And because it’s a single-pivot without a floating brake mount, the associated anti-rise (how much the suspension compresses under braking) is always going to be higher. For four-bar suspension diehards this could be a deal breaker, as it will settle the suspension more and make the Dreadnought firmer under certain braking conditions.
In contrast, GT’S four-bar configuration allows it to keep the anti-rise lower, so the rear suspension will sit higher under braking and remain more active. The flip-side is that less anti-rise also transfers more weight onto the fork. How you apply the brakes, and where you apply them, will influence the suspension too, so the simplistic trope – single-pivot bad, four-bar good, six-bar better – doesn’t really hold water.
The bikes have more in common than they have differences, though. Both are 29er enduro bikes designed around 170mm-travel forks.
Both also deliver on the claimed rear-wheel travel – always good to see. Both bikes have space in the front end for a water bottle and both are available in four frame sizes. At 15.99kg (35.25lb) the Dreadnought is a tad lighter than the GT and we should point out that the weights in this test are with our control tyres and Cush Core XC inserts (150g) fitted to the rear tyres.
So we have two bikes that share a similar design concept, but take different approaches. It’s time to find out which one will get you to the finish line first.
CONTROL TYRES