Our Bike Check feature is back with another beauty from the travelling circus that is the UCI World Cup Downhill. Shot by our brilliant regular freelance photographer James Vincent at Fort William in the Highlands of Scotland; Vincent zoomed in on Austrian Pro Downhiller David Trummer’s great-looking Mondraker Summum Carbon RR downhill race bike to capture all of the important details that help make it such a capable campaigner.
First off, a quick introduction to David Trummer. Hailing from Austria the 27 year old has had some impressive results in his racing career already, including a brilliant Silver medal at the 2020 World Downhill Championships on home ground at Leogang in Austria where he finished second only to Scotland’s Reece Wilson (see his own Bike Check from Fort William HERE). One of the most consistent racers on the circuit, David backed-up his 2020 Worlds silver medal in 2021 with top 15 performances at nearly every round of the UCI World Cup before rounding out the season with another good showing at the 2021 World Championships, where he finished 8th.
David Trummer’s Mondraker Summum Carbon RR is tuned and ready to race.
Trummer moved over to the MS Mondraker pro downhill team at the start of 2022 and has very quickly gelled his new Summum race bike. Leading up to the 2022 race season David worked closely with the design and engineering team at Mondraker along with the MS Mondraker team mechanics to fine-tune the ride of his Summum, harvesting precise suspension telemetries to help inform how best to set up the bike to suit the demands of all race tracks. Somewhere along the line of those pre-season testing sessions Mondraker retro-fitted a chain idler to the Summum; you may be aware for the latest trend that has swept through the race pits during the past couple of seasons – the trend for high-pivot suspension configurations? A high-pivot suspension setup moves the bike’s main pivot high above the chainring and the rear wheel axle to encourage and enhanced rearward axle path through the travel of the rear suspension.
Trummer in action on the demanding Fort William World Cup Downhill.
One of the potential drawbacks of such a configuration is chain growth and pedal kickback – as the rear axle travels through its suspension the chain tightens and pulls back on the cranks. Now, the bike brands running high-pivot suspension fit an ‘idler’ which is an extra jockey wheel placed above the chainring, eliminating those issues. The Mondraker Summum is somewhat of an enigma when it comes to running an idler as there’s no high-pivot configuration on the Summum, just the idler. The bike is identical to the 2021 version save for this additional idler; I’ll be interested to see what comes next? Perhaps an all-new model with a high-pivot configuration? In the meantime the addition of an idler must have brought some benefits to how the current suspension platform performs, I’d guess eliminating some pedal kickback?
While the Summum isn’t a high-pivot bike, Mondraker have retro-fitted a chain idler to help prevent pedal kick-back.
The chain idler on Trummer’s Summum is a new addition for the 2022 season.
Carbon frames on the World Cup scene are becoming more of a rarity these days, a reflection on the commercial viability of full-on downhill bikes maybe? We’ve seen big brands like Trek revert back from carbon downhill rigs to alloy as the Enduro bike market boomed and the downhill bike market contracted; in some cases it’s just not cost-effective to tool up for a carbon frame production for a fairly small run of frames. There’s no such scenario with Mondraker – the Spanish brand was founded by a talented former international downhill campaigner and their passion and knowledge of downhill runs deep throughout the organisation; this keeps them committed to carbon downhill bike production.
The Summum is constructed from Mondraker’s Stealth Air carbon.
The Summum’s chassis made from Mondraker Stealth Air Carbon is a thing of beauty and is lightweight too with the frame weighing 2800g (without the shock). At the heart of the Summum is their ZERO dual link suspension design which essentially facilitates a floating shock between the two suspension links, allowing the shock to compress from both ends; the result is rear suspension that is extremely sensitive on small bumps while also being big hit capable. It goes without saying that this Mondraker downhill bike features their ‘Forward Geometry’. Why is that so obvious? Because Mondraker were the absolute pioneers when it came to establishing this geometry concept and it’s perfectly suited to the specific demands of downhill racing. It’s the same design principle that we’ve seen every other bike brand arrive at subsequently, increasing stability at speed, providing better front wheel control and dramatically improving front tyre grip.
Part of the MS Mondraker team Trummer’s Summum carries the appropriate livery.
Forward Geometry is now in its ninth season but the evolution doesn’t stand still. Most recently Mondraker have introduced shorter fork offsets to match their existing Forward Geometry. After extensive testing they have proved that shorter fork offsets give the biggest benefits in combination with the Forward Geometry concept, giving super-responsive and direct steering thanks to a short stem and long reach top tube. This design principle gives the Summum Carbon RR a more playful ride, and a feeling that you can attack harder into the corners.
Pioneers of today’s modern trail geometry, Mondraker label their own design principle as ‘Forward Geometry’.
Eagle-eyed readers may have already spotted that David Trummer is running his Summum as a ‘mullet bike’ (business up front, party at the back) consisting of a 27.5” diameter rear wheel and a 29” diameter front wheel which gives him all the advantages of a faster-rolling front wheel with a more agile rear wheel that he can throw around tight turns a little easier. The MS Mondraker Racing Team are supported by Shimano components and Fox suspension, with eThirteen providing the mis-matched mullet wheelset; traction and control is taken care of by Michelin tyres and a Renthal cockpit keeps David in control at race-speed. Scroll through the rest of James Vincent’s photos to see all of the specification details…
Upfront there’s a capable Fox 40 29 Float FIT GRIP2 EVOL Factory Kashima fork, boasting 203mm of travel.
A timing chip attached to every racer’s fork ensures finishing times are accurate to the nearest hundredth of a second.
The MS Mondraker team runs full-Shimano groupsets on the Summums; their Saint drivetrain more than meets the demands of downhill racing.
A compact Shimano Saint 10-speed rear derailleur with clutch mech keeps the Summum’s chain firmly located while providing flawless gear shifts.
Shimano XTR brake levers paired with 4-piston hydraulic calipers provide plenty of stopping power.
The Mondraker Summum Carbon RR is spec’d with an eThirteen wheelset; there’s a 29″ upfront and a 27.5″ rim out back.
The MS Mondraker team are on Michelin tyres; Trummer is running a DH22 upfront and a Wild outback.
Tyre choice for Fort William was tricky, with riders trying to strike a balance between speed and grip.
With a lower-profiled central tread pattern and larger outer side knobs this Michelin Wild tyre was fast on the rocky upper part of the course but grippy in the woods.
The UK’s Oliver Morris, racing for MS Mondraker onboard the same Summum model as Trummer.
The stunning Mondraker Summum Carbon RR carried Trummer to an excellent 20th finishing position at the Fort William World Cup.
- Frame: Summum Stealth Air full Carbon, Zero Suspension System, 200mm travel, Forward Geometry, Carbon Monoblock upper link, SuperBoost 12x157mm rear axle, 83mm BSA bottom bracket, HHG internal cable routing, MAX. capacity dual raw Enduro bearings, shock mudguard, ISCG 05, custom frame protectors.
- Shock: Fox DHX2 Factory Coil Shock 225x70mm. Settings: high and low-speed compression, high and low-speed rebound, spring preload. Super light steel (SLS) spring. Trunnion top mount, 30x8mm bottom bushing
- Fork: Fox 40 29 Float FIT GRIP2 EVOL Factory Kashima, 203mm, air spring, 1-1/8” steerer tube, 20x110mm axle, offset 56mm. Settings: high and low-speed compression, high and low-speed rebound, air preload
- Cassette: Shimano 10-Speed
- Derailleur: Shimano Saint 10-Speed
- Shifter: Shimano Saint 10-Speed
- Cranks: Shimano Saint Hallowtech II MTB
- Chainring: Shimano Saint 36T
- Chain Device/Idler: Mondraker Prototype
- Brakes: Shimano XTR 4-Piston Caliper
- Brake Levers: Shimano XTR
- Rotors: Bolt-On
- Wheels: eThirteen LG1+ DH Rims – 27.5” Rear/29” Front, eThirteen Hubs – LG1 Race Front/TRS Race Rear Hub
- Tyres: Michelin Wild 27.5” Rear, Michelin DH22 29“ Front
- Stem: Renthal Direct Mount
- Handlebar: Renthal Fatbar35 30mm Rise
- Grips: Renthal Lock-on
- Saddle: SDG i-Beam
- Seatpost: SDG i-Beam
- Pedals: DMR V-Twin Clipless
- Fender: Fox Fork 40 Mud Guard
Written by Johnny Dodgin
Photos by James Vincent
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