How to Choose Mountain Bikes
Tern Orox S12 Electric Bike
$6,599.00
Members get an est. $659.90 in rewards
Explore new ground with the Tern Orox S12 electric bike. Outfitted with a Bosch Performance Line CX motor, the bike powers up hills and can carry lots of gear for multiday trips far from home.
Key Details
E-Bike Classification
Class 1: pedal assist up to 20 mph
Motor
Bosch Performance CX, max speed 20 mph (US)
Battery Capacity (Wh)
725 watt hours
Weight
Bike without battery: 73 lbs. 3.2 oz.
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- Shimano Deore XT 1 x 12-speed groupset for fast and precise shifting
- 27.5 in. stud-compatible Vee Snowball tires take on even the toughest conditions
- Hill-attacking Bosch Performance Line CX motor provides up to 85 Nm of torque and 340% support
- 725 Wh battery provides a range of 52 to 91 miles
- Dual-battery system draws from up to 2 batteries for ultralong range (second battery not included)
- Bosch Smart System with ConnectModule lets you access and control advanced functions like eBike Alarm and eBike Tracking
- Splash- and dustproof Kiox 300 color display with LED remote for intuitive control
- Powerful and responsive Magura 4-piston hydraulic brakes
- EFBE-certified safe and reliable for massive hauls, with a Max Gross Vehicle Weight of 210 kg (462 lbs.) on pavement and 180 kg (397 lbs.) off-road
- 2 frame sizes to fit riders 5 ft. 1 in. to 6 ft. 5 in. (155–195 cm) tall, and weighing up to 286 lbs. (130 kg)
- Weight: 73 lbs. 3.2 oz. without battery
- NOTE: Specs and images are subject to change based on component availability
Imported.
This e-bike comes with Coast to Coast Support, which includes:
New bikes go through a normal break-in period, after which they should be readjusted. All electric bicycles sold at REI include free adjustments for the defined period (one year after purchase date for non-members, or two years for REI Co-op Members)—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation, chain lubrication and e-bike firmware updates. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
UL2849 certified
View all Tern Fat-Tire Bikes- 1 year of free adjustments (see more below)
- In-store bike assembly
- Pickup in store or curbside
- Bike experts available at 170+ bike shops
- An additional year of free adjustments on e-bikes
- 20% off shop services
- Free tubes with purchase of flat tire repair (Co-op Cycles brand tubes only; tube must be installed at time of purchase)
New bikes go through a normal break-in period, after which they should be readjusted. All electric bicycles sold at REI include free adjustments for the defined period (one year after purchase date for non-members, or two years for REI Co-op Members)—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation, chain lubrication and e-bike firmware updates. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
UL2849 certified
| Best Use | Bike Touring Backpacking |
|---|---|
| E-Bike Classification | Class 1: pedal assist up to 20 mph |
| Motor | Bosch Performance CX, max speed 20 mph (US) |
| Motor Type | Mid-Drive |
| Motor Torque (Nm) | 85 Newton meters |
| Battery Type | Lithium Ion |
| Battery Capacity (Wh) | 725 watt hours |
| Battery Removable | Yes |
| Charge Time (hrs) | 2.3-6 hours |
| Pedal Assist Range | 52-91 miles |
| Mountain Bike Style | Fat-tire |
| Frame | Tern Orox, 6061-AL, patented design, EFBE tested and approved |
| Step-Through | No |
| Bike Suspension | No Suspension |
| Fork | Atlas X, butted chromoly steel, EFBE tested and approved |
| Crankset | Tern Orox custom |
| Bottom Bracket | Motor Integrated |
| Shifters | Shimano Deore, 1 x 12-speed |
| Rear Derailleur | Shimano Deore XT Shadow+ |
| Rear Cogs | Shimano 10-51T, 12-speed |
| Number of Gears | 12 gear(s) |
| Brake Type | Hydraulic Disc Brake |
| Brakes | Magura MT5, 4-piston hydraulic disc, 203 mm rotor |
| Brake Levers | Magura MT5, hydraulic |
| Rims | Tern Atlas X, custom doublewall construction |
| Front Hub | Tern Atlas X, CNC body, disc cooling fins, Boost thru axle, integrated Tern Tool with 5 mm hex/T20 Torx |
| Rear Hub | Tern Atlas X, CNC body, disc cooling fins, Boost thru axle, Syntace X-12 standard |
| Wheel Size | 27.5 inches |
| Tires | Vee Snow Ball, 27.5 x 4 in. |
| Tire Width | 4 inches |
| Handlebar Shape | Riser Bar |
| Handlebar | Level Nine, AL-7050, 800 mm, riser, eMTB approved |
| Stem | Level Nine, 45 mm (M), 65 mm (L), Syntace VR-3 certified |
| Seat Post | Syntace P6 AL7050, 34.9 mm, Syntace VR-3 SP-approved |
| Saddle | Ergon SM, E-Mountain Sport, chromoly rail |
| Pedals | MTB, nonslip |
| Headset | FSA, 1.5 in., angular-contact bearings |
| Chain | KMC 12-speed, for e-bike, EPT corrosion-resistant coating |
| Weight | Bike without battery: 73 lbs. 3.2 oz. |
| Bike Weight | Bike weight is based on median size, as sold, or the average of two median sizes. |
| Gender | Unisex |
| Sustainability | Contains recycled materials |
Tern Bikes (237651)
| M | L | |
|---|---|---|
| Height Range | 5’1″ - 6’1″ | 5’5″ - 6’5″ |
| Reach | 610 - 660 | 670 - 730 |
| Seat Tube Center-Top | 710 - 990 | 765 - 1045 |
| Standover Height | 700 | 700 |
Sizing Notes
Measurements are stated in millimeters unless otherwise indicated.
How we measure bikes
- Standover Height Standover Height is a measurement from the ground to the top of the top tube, measured at the midpoint of the top tube.
- Reach Reach is the horizontal distance from the center of the cranks to the center of the head tube, measured at head tube level.
- Stack Stack is the vertical distance from the center of the cranks to the center of the head tube, measured to the top of the head tube.
- Effective Top Tube Effective top tube is the distance from the center of the head tube to the center of the seat tube/seat post, measured parallel to the ground.
- Seat Tube Center to Top Seat Tube length is the measurement of the seat tube, from the center of the cranks to the top of the seat tube.
- Head Tube Length Head Tube Length is measured from the bottom to the top of the head tube.
- Head Tube Angle Head Tube Angle is the acute angle between the head tube and the ground (measured towards the rear of the bike)
- Seat Tube Angle Seat Tube Angle is the acute angle between the seat tube and the ground (measured towards the rear of the bike).
- Bottom Bracket Height Bottom Bracket Height is a measurement taken vertically from the ground up to the center of the cranks.
- Wheelbase Wheelbase is the measurement from the center of the front axle to the center of the rear axle.
- Chainstay Length Chainstay Length is the measurement from the center of the cranks to the center of the rear axle.
- Fork Offset Fork Offset, or rake, is the distance from the front axle to a line drawn parallel to the center of the head tube or steering axis.
