The MS Mondraker team are at the 2023 UCI World Champs in Fort William this weekend, riding an all-new frame design that we first spotted in Lenzerheide earlier this year. Now, the sock is off, revealing a new VPP suspension linkage wherein the shock is driven by the swingarm itself – not dissimilar to the layout utilized by the recently released Mondraker Neat eMTB.
Brook MacDonald’s Prototype Mondraker Downhill Bike
Getting a closer look at Brook MacDonald’s ride, we can see that this is one of the most uniquely adjustable downhill bikes on the World Cup circuit. In addition to chainstay length adjustment, shock mounting position adjustment, and a wide range reach adjust headset, the new frame is able to run a maximum of three cnc-machined braces on the swingarm for a multitude of different stiffness profiles, and it has a modular bottom bracket that allows for multiple BB positions.
This latter feature gives the team the ability to adjust effective rear-center length without impacting leverage, while simultaneously altering reach, BB height, and of course the bike’s anti-squat. No other bike, at least on the world cup circuit, has this level of adjustability.
Brook MacDonald’s mechanic, Jake Ireland, tells us that there is another key advantage to having a machined bottom bracket module, besides the adjustability it brings. It also gives Mondraker tighter control over the location of the BB relative to the frame pivots and dropouts, something that is absolutely critical to the kinematic. That tighter control comes from the fact that the BB isn’t part of a welded structure.
Like the previous Summum DH frame, the new bike runs a short-link four-bar linkage that delivers a virtual main pivot location. While the shock was previously driven by the lower link, it is now mounted to the swingarm, with three possible mounting locations giving subtly different ride characteristics. It is compressed from both ends simultaneously as the bike is pushed through its rear wheel travel.
We are told the linkage was developed with the engineers’ detailed knowledge of how the Fox DHX2 coil shock works. It has a very progressive leverage curve, and all members of the MS Mondraker Team – Brook MacDonald, Tuhoto-Ariki Pene and Eleonora Farina, were running this coil shock.
“When we were testing, we found that the bikes that felt best weren’t necessarily the ones that were firing for a specific number for anti-rise, but the ones that were consistent, so they felt predictable the whole way through the travel. It is a little under 100%, and relatively consistent”
Jake Ireland, Brook MacDonald’s Mechanic
We are told the mounting location doesn’t influence the overall progression of the frame, but it does alter the leverage ratio in the early phase of travel. Brook opts for the position that gives a slightly higher starting leverage ratio for a softer early stroke.
There’s more…
Brook’s team mate, Tuhoto-Ariki Pene is also running the new setup – his bike is sporting an OChain. The OChain serves to reduce pedal kickback by dissociating rearward chainring rotation from the crankset. Brook’s bike is lacking an OChain, but his mechanic, Jake Ireland, tells us that the team is “experimenting with other methods that mean they don’t need to use an OChain”.
Intriguing.
A closer look at the rear hub reveals a prototype from e*Thirteen. The LG1 DH carbon rim is laced to a hub shell that is over-sized on the drive side. This is not unusual in itself, but the larger diameter section looks to be even larger than that seen on e*Thirteen’s production hubs, and it looks to extend further inboard. This leads us to speculate that the new hub shell could be housing some new technology, such as a decoupler mechanism, that could prevent the rear hub from engaging during potential pedal kickback events.
That said, we are told there are no electronics on the bike, so it’s difficult to see how exactly such a mechanism could be timed appropriately.
We reached out to E*Thirteen for comment. They say there will be more info available on this hub next year. Their comment for now is:
“The primary design goal with that hub is to eliminate pedal kickback and it does just that. The whole MS Mondraker crew has been super helpful in helping log loads of hours and learn quite a bit”
E*Thirteen
This is fairly fascinating. We look forward to learning more about how the mechanism is able to differentiate between pedaling and suspension compression-induced chain growth events.
The LG1R DH carbon rim is home to a prototype Michelin DH16 tire, which is fairly similar to the Michelin Comp 16 if anyone remembers that, only better to the tune of 20 years worth of tire development. I can tell you it is intended as a dry conditions tire, it has an extraordinarily soft rubber compound, and that the MS Mondraker Team is very happy with its performance.
Brook MacDonald’s Setup
- Fox 40 Factory Downhill Fork, set up firm with 97 PSI and 5 tokens
- Fox DHX2 Coil Shock, 500 lbs Spring
- Shimano XTR levers with Shimano Saint Calipers (203mm front and rear)
- Tire pressures in the mid twenties
- Frame reach: 473mm (Brook is 5ft 8″ tall)
- Chainstay Length: 450mm
- Head angle: 63°
- Bar: Renthal Fat Bar Alloy 35mm – 780mm wide
- Renthal Grips
- 165mm Shimano cranks
- SDG Saddle with I-Beam rails
