Fast and agile, Cortex is a trail riding, down-country, all terrain mountain bike for seriously epic days out. It comes alive on long technical descents with 120 mm rear travel, big wheels and a stiff responsive frame.With bang up to date geometry, Cortex is confidence inspiring with a playful character. Stand up and mash on the pedals out of turns, manual sections of trail and pop off tree stumps, rocks and roots. Smash out short and loose technical climbs, flat out descents and tight techy singletrack sections. The harder you push the bigger you grin.
At a Glance
- Fast and agile short travel full sus 29er; perfect for mixed terrain and day long epics
- Frame: Sonder Cortex 120 mm travel, hand-welded 6061 double butted aluminium
- Fork: Rockshox Recon RL Silver / 130mm / 29
- Rear Shock: Rockshox Deluxe Select+ / 190x45
- Groupset: SRAM SX Eagle, 1x12, 11-50
- Brakes: SRAM Level
- Seat Post: Love Mud Membar, 31.6 mm, 400 mm
- Wheelset: Love Mud Hobo 29er
- Up to date geometry for trail bike agility and enduro bike stability
Cortex frameset is hand-welded from 6061 double butted aluminium with a tapered ovalised top-tube and large section down-tube for a stiff chassis with just enough compliance to get you out of trouble. 66 head angle, 74.5 seat tube angle, 40 mm bottom bracket drop and a 465 mm reach (size large). Cortex’s dialed in geometry and 2.6" tyre clearance offers a comfortable and efficient climbing position for big miles and a stable, spirited platform for smashing up descents...Read more
Why SX? SRAM Eagle drivetrains are designed, engineered and manufactured to work as complete drivetrain systems. Its 1x drivetrain is a solution that is built to be lightweight, strong and intuitive, with the gear range to ride on any terrain. SX Eagle provides the same Eagle performance benefits as NX Eagle, but at a lower price point. The main differences stem from the choice of materials and finish options, but functionally SX is fully compatible with SRAMs Eagle groupset.Read less
Up to Date Trail Bike Geometry
Trail bike Agility with Enduro bike stability, the Cortex has a confidence inspiring, stable and forgiving ride.
Metric Shock Standard
Designed around metric shock sizing standard, with lengthened shocks and shorter strokes that increase bushing overlap for more smooth, supple, sensitive and reactive suspension action.
Horst link suspension design
The tried and tested Horst link suspension design allows the suspension to stay active when braking.
Clearance for up to 29 x 2.6in tyres.
Internal Cable Routing
Internal routing in the front triangle for clean lines.
|Build||Cortex SX Eagle|
|Frame:||Sonder Cortex Frame|
|Fork:||Rockshox Recon RL Silver / 130mm / 29|
|Shock:||Rockshox Deluxe Select+ / 190x45|
|Headset:||Love Mud Rumour / ZS44-ZS56|
|Brake Front:||SRAM Level / Direct / 850mm|
|Brake Rear:||SRAM Level / Direct / 1800mm|
|Rotor Front:||Avid Centreline Rotor / 180mm|
|Rotor Rear:||Avid Centreline Rotor / 160mm|
|Rear Mech:||SRAM SX Eagle Rear Derailleur / 12 / Long|
|Rear Shifter:||SRAM SX Eagle Trigger Shifter|
|Chainset:||SRAM SX Eagle Crankset / Powerspline / 170mm / 32|
|Bottom Bracket:||SRAM Powerspline Bottom Bracket / 73mm / 118mm|
|Chain:||SRAM NX Eagle Chain / 118 Links|
|Stem:||Love Mud Piskie Stem / 31.8mm / 35mm|
|Seatpost:||Sonder Seatpost / 31.6mm / 400mm|
|Saddle:||Sonder Abode / Black|
|Tape/Grips:||Sonder Clutch / Black|
|Wheels:||Sonder Nova 29 Wheelset / Shimano|
|Front Tyre:||WTB Vigilante / Light High Grip / 29 / 2.5|
|Rear Tyre:||WTB Trail Boss / Tough Fast Rolling / 29 / 2.4|
|Frame:||S: 1.97 kg; M: 2.0 kg; L: 2.1 kg; XL: 2.14 kg|
|Pedals not included with full builds|
SizingIt is important to get the right size bike, if the bike fits it will be faster, more comfortable, and easier to handle. You can also take into consideration the standover height to ensure you pick a bike that will be a good fit. If you measure your inside leg and ensure there is a minimum of an inch from the toptube to your crotch this will give you enough seatpost adjustment to find your optimum saddle height. Generally we recommend:
- Riders between 5ft 2in and 5ft 7in
- Riders between 5ft 6in and 5ft 10in
- Riders between 5ft 9in and 6ft 2in
- Riders of 6ft 2in +
|ST - Seat tube||400||425||465||485|
|TT - Top tube||587||608||636||658|
|HT - Head tube||100||105||115||125|
|HA - Head angle||66||66||66||66|
|SA - Seat angle||74.5||74.5||74.5||74.5|
|CS - Chainstay||442||445||447||450|
|BB - BB drop||40||40||40||40|
|FO - Fork offset||51||51||51||51|
|WB - Wheelbase||1169||1191||1220||1244|
|SO - Stand over||TBC||TBC||TBC||TBC|
|RE - Reach||420||440||465||485|
|SK - Stack||602||606||615||625|
|Fork Axle to Crown||540||540||540||540|
|Weight: S: 2.73kg; M: 2.91kg; L: 3.05kg; XL: 3.11kg|
|Hydroformed and custom butted alloy frame tubing|
|Internal cable routing|
|Rear Shock: Rockshox Deluxe Select+ 190 x 45 mm|
|Horst link suspension layout|
|120 mm rear travel; 130 mm fork travel|
|Clearance for up to 29” x 2.6 in wide tyres|
|73 mm BSA threaded bracket shell|
|148 x 12 mm rear thru-axle|
|31.6mm seat tube, 34.9mm clamp|
|ZS44/28.6| ZS56/40 headset (frame and rear shock does not come with headset)|
Bike Radar have their eyes set on the new Sonder Cortex"Sonder has added to its bicycle range with the Cortex trail bike — a 120mm travel full suspension 29er that starts at £1,500 and is designed, it seems, to do just about anything."
We handed the Cortex over to Guy Kesteven for some real trail testing.
Cortex is a light, well-shaped frame that balances instant familiarity with extra confidence on faster, rowdier trails. Add an easy to set up fork, decent stop, go and finishing kit rolling on sturdy wheels with a properly surefooted front tyre and you’ve got a great package for the price.
Andi at Singletrack gets an exclusive first ride review of the latest 120mm travel full-suspension bike from Sonder. Meet the 2020 Sonder Cortex.
"While riding the Sonder it felt just as fast as my big bike but sharper to corner, easier to hop and overall a hell of a lot of fun to ride, and I cannot wait to get on it again."
Read the full first ride review over on Singletrack.