The Resurgence of High Pivot Suspension Design

Bikes with a high main pivot and an idler pulley have had success throughout the years, but have never truly broken into the mainstream. We're used to seeing FSR, VPP, traditional single pivot, and DW link configurations on the podium, with high pivot bikes not consistently featuring at the pointy end of the world cup downhill pack. But, recently there's been a resurgence of the design.

The bike of the moment is the Commencal Supreme that, under a young and relatively unknown Amaury Pierron, has won the last two World Cup rounds. There's also Myriam Nicole, who has taken a 1st and two 2nd placings in 2018, along with first-year junior, and another Frenchie, Thibaut Daprela netting the same results. So the high pivot Supreme is the most successful bike this year so far, leading elite men, elite women, and second overall for the junior men on the World Cup circuit.





What is a high pivot bike, and why?




A high pivot can create a rearward path at the axle, which, in theory, allows the rear wheel to more easily move away from, and then over, an obstacle. The high pivot position, however, leads to a lot of chain growth as the axle moves away from the chainring, which will cause a lot of pedal kickback. This is when the cassette sprockets move away from the chainring and the cranks are pulled backward as the chain is put under tension, a trait that can keep the suspension from doing its job freely.

But there is a solution - the simple addition of an idler pulley close to the pivot point that routes the chain up and over it. High pivot bikes equipped with idlers have characteristics that are unique: the lack of chain growth, along with the rearward axle path, allows the wheel to float over bumps in a very different way than other designs. The downsides can be poor pedaling performance, extra drivetrain complication, and high anti-rise values that essentially pull the suspension down into the travel and affect the sensitivity of the suspension. This anti-rise, in particular, is a love-hate characteristic. Some moan about it locking out the suspension, but generally I prefer the way it conserves the geometry of the bike when braking on steep downhills - this negative can also be 'out ridden' in certain ways, which I will get to in a future article.

High main pivot designs can, in fact, tune the characteristics of anti-squat, anti-rise, etc., by changing the location of the idler. Commencal has been seen playing with this at recent World Cups races by lowering the idler below the main pivot, a change that would provide more anti-squat (and also more pedal kickback).




High pivot history

So, Commencal has the bike of the moment, but the theory is nothing new. Let's take a look back over the last twenty years to see the movers and the shakers in the high pivot world.





















The new school?

Within the last two years, there have been a number of other bikes pop up. Don't call it a comeback as they never went away, but many of these designs are generally from the niche, shed engineers, and the weird or short-lived marques. It is interesting to see Commencal, Norco, and apparently GT put some serious investment and confidence in these bikes, though.








GT Prototype / 2020? - The GT sled has been seen at numerous races this year, and we can only imagine it will be sent into production. Remember that Ghost from 2013? I thought it looked familiar. Also, the K9ine was an interesting bike designed by Luis Arraiz, who now works at CSG, the parent company of GT.

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Final thoughts

It will be interesting to see how these bikes are accepted in the future. Most of the machines from the past that are featured here died off for one reason or another, be it they were niche racing rigs, brands that couldn't manage themselves, or simply unappealing bikes that were a hard sell to fickle consumers. The biggest cull of these bikes was likely due to wheel size and standards changing so fast that small brands couldn't afford to keep up. Ironically, if win-on-Sunday-sell-on-Monday still holds true, the 29" wheeled Commencal and Norco could be some of the best selling downhill bikes of 2018.

Initial impressions of the Commencal has been extremely positive, and the Norco has just landed for testing. Both bikes are going head to head against some other 29" downhill bikes over the next few months, so expect the reviews to start landing soon.

What weird and wonderful high pivot bikes did we miss from the past? Let us know in the comments.