High Pivot MTB
Here at Deviate, we like to do things a little differently - hence our name. We are fully committed to the benefits of high-pivot suspension, because we think it’s the best suspension design around for mountain bikes. We’d like to explain why.
A long time ago…
In the very early nineties, the idea of a perfectly functioning full-suspension mountain bike existed mostly in the realm of the dreamer, or the madman. They did exist, of course (the Victorians came up with full suspension bicycles in the late nineteenth century, after all) - but they weren’t necessarily fit for purpose. Full suspension mountain bikes were frequently flexy, they were mostly either awful up hills or awful down them, and god they were expensive. But slowly, thanks to those same dreamers and madmen, a few key designs came to the fore. Many have carried on to this day - the single pivot; the Horst link; the multi-link. But a few of them seemingly didn’t really catch on at the time despite considerable potential - one of which was a suspension design which featured a high pivot. Over the past few years, though, high pivot designs have had something of a renaissance, especially in downhill racing.
An increasing number of bike manufacturers have been making DH waves recently with their high pivot bikes - even Trek is getting in with the High boys. But the key difference between modern designs and those of yore is that they all use an idler gear to bring the chainline up to the pivot.
In the dim and distant past (well, the nineties, anyway), the idea behind high pivot point bikes was two-fold. When you weren’t pedalling (on a descent) the high pivot rear end would provide a lovely bump-smoothing suspension action. But when you started pedalling, the suspension would pull itself together, stiffen up and become bright and perky for the hills. Or at least, that’s what the marketing shouted to great effect for bikes such as GT’s RTS. But this arrangement introduced some pretty strange handling characteristics - pedal kickback being chief among them - and it meant that high pivot designs were quickly superseded by others with more consistent action whether you were pedalling or not. Especially as rear wheel travel has increased over the years, and the design’s kinematic flaws have become more apparent.
In most suspension designs, as you extend the suspension through its travel, the chain stays lengthen, to a greater or lesser extent. When pedalling, this exerts a force on the chain, which pulls on the chainring. The rider can feel this as the pedals ‘kicking’ underneath them. Conversely, if you stamp on the pedals, you’ll stiffen the suspension up. Not exactly ideal.
Now - thankfully - shock, fork and bike technology has progressed - along with the terrain we ride, and how we ride it. Crucially, single chainring setups have become commonplace. So it’s much easier to run a bike with an idler, without all those fiddly chainrings and that pesky front mech getting in the way.
What makes idlers and high pivots ideal?
Well, first of all, let’s look at the high pivot itself, and what’s so great about it from a riding point of view. Firstly, locating the pivot some way above the chainring gives the suspension a rearward axle path which is rather useful when riding lumpy stuff.
Essentially, the wheel moves in a rearward path, and echos the direction of the incoming hit. This gives the suspension more time to compress, letting the damper do its work. On a conventional bike, with a lower pivot, the wheel moves more vertically, so there is a component of the impact force that is pushing you backwards and trying to stretch the chainstays. Basically, high pivots help to stop the suspension from getting hooked up on square-edged hits, and they produce superior suspension performance. It’s also possible, depending on the pivot placement, to dial in more anti-rise, which is the bike’s innate ability to resist extension under braking (so-called brake jack), and keep the suspension supple. And that rearward axle path, coupled with the anti-rise can also help to keep the wheelbase constant.
Ben Jones, Deviate co-founder, expands:
“The Highlander has around 127% anti-rise, which means the suspension compresses slightly under braking. This results in a more stable geometry, because there is a reduced weight transfer to the front wheel, so you don’t get nearly as much front wheel dive - and you can therefore run a little less low speed front damping. You do lose some small bump sensitivity under braking, as there is more load on the shock, and you need to overcome this ‘preload’ before the suspension moves - but this is a small price to pay in a small aspect of suspension performance when compared to the huge benefits everywhere else.”
What’s more, the amount that the rearward axle path on the Highlander extends the wheelbase is broadly the same as the amount the fork decreases it as it runs through its travel. When you haul on the brakes the bike remains level and controllable, and the wheelbase remains more constant.
All sound reasons for running a high pivot - except for all of that pesky pedal kickback we mentioned earlier. And this is where the idler comes in.
Chris Deverson is Deviate’s cofounder and engineering übermensch: “I first rode a high pivot idler bike - a Zerode G1 - when I was guiding for Vertigo Bikes in Queenstown, New Zealand. From an engineering perspective, the suspension design makes so much sense, but for the riding I wanted to do, the pivot placement felt too high, and it resulted in huge geometry changes. At the time, high pivot idler bikes were really coming to the fore in DH, but it seemed obvious that the potential for big-mountain trail bikes was massive.
“By running an idler, we effectively remove the pedal kickback and reduce chain growth to negligible amounts. And we’ve tweaked the precise position to give the best riding bike possible in the widest variety of scenarios.
Essentially, any bike is a compromise - you have to work around the vastly uneven forces caused by two huge meat pistons turning the pedals, the fact that the rider is vastly heavier than the bike, and that they move around the whole time. The perfect bike needs to pedal well, to climb, to perform beautifully on the descents, and to behave in a predictable and controlled manner both under braking and acceleration. Running the high pivot with an idler lets Deviate do all that, and more. The system could lend itself, with appropriate tweaks, to disciplines ranging from XC all the way through Enduro to DH.”
“Now that most drivetrains don’t run front mechs, High Pivot is simply the best choice for all sorts of mountain bike applications” - Chris Deverson, Deviate cofounder
Deviate’s first bike, the Guide, was a gearbox-driven high-pivot machine, which was designed for all-day, big mountain riding with the bare minimum of maintenance, and the best suspension system going. But it’s not quite as easy as just slapping a high pivot on a frame, and running an idler as close to it at possible. The precise position of both has a huge effect on how the bike performs. Place the pivot too high, and the bike feels like it’s folding underneath you; too low, and the beneficial features of the design are diminished, or lost altogether. The Deviate design sits in a sweet spot - it’s not the highest nor the lowest available, but it’s perfect for the all-rounder Chris intends Deviate’s bikes to be. And the huge amount of experience gleaned from designing the Guide fed directly into the design of the Highlander.
“We took the Guide prototypes over to the Alps,” said Ben, “and put hundreds of hours into them. The only major tweak we needed to do was to increase the size of the idler pulley, as the smaller ones were too noisy and wore too fast. So with the Highlander, we could take all that research, adjust the idler position to suit the bike and dial in exactly the riding characteristics we wanted - to make the Highlander the true one bike quiver.”
That vast high-pivot and idler design experience feeds directly into the Highlander to make a bike with huge advantages in terms of stiffness, smoothness of operation and low maintenance compared to others.
“We made sure that there’s no need to join chains with our system - a regular chain fits, no problem,” said Chris. “We also made sure that the suspension setup generates a leverage ratio that works brilliantly with both coil and air shocks - whilst having anti-squat performance designed for efficient pedalling, and anti-rise under braking to keep the geometry stable and keep the rider’s weight centred when riding aggressively. We’ve even designed it with a linkage you can swap out to alter the suspension travel, which makes the bike even more versatile.”
The best of the best
Of course, all this attention to detail in the suspension department is echoed across the rest of the Highlander. We’ve made sure that the bike is truly one of the most exceptional, well-thought out machines on the market.
We don’t wish to brag, but we think that our top-quality carbon frame is one of the most beautiful available - and we’re not alone. It’s gloriously sleek, with huge standover. Our geometry is carefully thought out - modern, but balanced - to keep the ride poppy and fun, whilst making it planted when you’re giving it some beans.
Deviate’s bikes are also designed with an eye towards ease of home maintenance. We’ve kept to the most recognised ‘standards’ in the industry to make sure that other components fit easily. We’ve removed the fiddle, faff and rattle of internal cable routing (but kept the sleek aesthetics) by making a recessed channel along the top tube to hide the cables in, which also makes the frame stiffer.
There’s plenty of shock clearance, and standard mounts to fit a huge range of shocks. We’ve made room for even the longest dropper post - at full insertion - and we’ve given this and the rear mech internal tube-within-tube routing for easy installation and no rattles. We’ve designed in integrated impact and chainslap protection, a lower ISCG mount for a bashgoard or chain retention, and we’ve even made room for a water bottle *and* carry systems which mount to the cable channel bolts. What more could you want? Oh, you’d like to be able to change the Highlander’s travel between 140mm and 150mm simply by swapping a link? No problem!
At Deviate, the idea is always to make bikes that simply work. Bikes that need minimal fettling, but that deliver outstanding rides, time after time after time. We need exceptional performance and maximum reliability from a hugely versatile, unique bike with astonishing looks. We think we’ve done it - and we think you’ll agree.