Oso

Downhill Both Ways

  • 155mm 6.1" Rear Travel
  • 170mm 6.7" Front Travel
  • 29 / 27.5" Size specific wheelsize
  • Suspension

Oso

A whole new sport demands a whole new bike. Built from the ground up to deliver a new level of smooth, fast, and durable performance, the full-carbon-fiber Oso features our first-ever upper-link suspension dw-link platform. It stacks 155mm of rear travel with 170mm up front and is powered by a Bosch Performance line CX motor.

Empty Name 3

Geometry

The Oso doesn’t just lean into enduro ter­ri­to­ry. It drops in, elbows out and gog­gles down. The long wheel­base, roomy cock­pit and slack 64-degree head angle were inspired by our race-win­ning Rip­mo. And its size-spe­cif­ic seat angles allow rid­ers of any height to bang out climbs in com­fort with­out wast­ing a watt.

2022 8 Oso Detail Shots5870

Size specific chainstays and wheel configuration

Large and extra large Oso frames are built around match­ing 29-inch wheels, while small and medi­um frames get the mixed-wheel treat­ment and short­er chain­stays. That keeps the Oso from ever feel­ing unwieldy. In fact, it’s pret­ty damn wieldy.

2022 8 Oso Detail Shots5866

Why Bosch?

The Bosch Per­for­mance line CX has a qui­et, pow­er­ful 85 NM dri­ve unit, which offers the most nat­ur­al-feel­ing accel­er­a­tion since the inven­tion of grav­i­ty. On top of that, you get Bosch’s two-year war­ran­ty, a net­work of 2,400 deal­ers across the U.S., UL safe­ty-cer­ti­fied bat­ter­ies, and its car­bon-neu­tral oper­a­tions. So, in case you were won­der­ing, that’s why we went with Bosch.

2022 8 Oso Detail Shots5868

Big Battery

With a deep 750wh bat­tery on sizes medi­um thru XL and a 625wh bat­tery on the small, the Oso is built to go big and still have enough juice left to go home.

2022 8 Oso Detail Shots5875

Upper link suspension

It may look a lit­tle dif­fer­ent, but the Oso’s Upper Link sus­pen­sion is still dw-link. That means it packs all the trac­tion and effi­cien­cy you’d expect from an Ibis, but with a more sup­port­ive lever­age curve to keep up with all the demands of a full-pow­ered e‑bike.

Wheels learn warranty large

Seven Year Warranty

We stand behind our prod­ucts. If it’s our fault, we’ll fix it. Our alu­minum frames are backed by the same 7 year war­ran­ty and excel­lent cus­tomer ser­vice as our car­bon products.

Build Your Oso

Oso

Select a Build

Pick Your Size

The Oso doesn’t just lean into enduro territory. It drops in, elbows out and goggles down. Large and extra large Oso frames are built around matching 29-inch wheels, while small and medium frames get the mixed-wheel treatment and shorter chainstays.

  • 64° Head Tube Angle
  • 77-79° Seat Tube Angle
  • 439–444mm Chainstays
Geo oso

170mm Fork (584mm axle to crown)

Nominal Size   Small Medium Large X-Large
Seat Tube Length A 394 15.5 415 16.3 415 16.3 427 16.8
Top Tube Length B 573 22.6 607 23.9 638 25.1 669 26.3
Head Tube Length (4mm stack of lower cup not included) C 90 3.5 106 4.2 122 4.8 139 5.5
Chainstay Length D 439 17.3 439 17.3 444 17.5 444 17.5
Seat Tube Angle E 77° 77° 77° 77° 78° 78° 79° 79°
Head Tube Angle G 64° 64° 64° 64° 64° 64° 64° 64°
Wheelbase H 1206 47.5 1242 48.9 1294 50.9 1341 52.8
BB (L/XL with Maxxis Minion 29x2.5WT tires, S/M with 27.5x2.5WT rear tire). 341 13.4 341 13.4 340 13.4 340 13.4
BB Drop K 31 1.2 31 1.2 31 1.2 31 1.2
Stack I 621 24.4 635 25 650 25.6 665 26.2
Reach J 430 16.9 460 18.1 500 19.7 540 21.3
Saddle Height F 655 25.8 705 27.8 765 30.1 820 32.3
Standover 677 26.7 714 28.1 729 28.7 731 28.8
Trail 132 5.2 132 5.2 132 5.2 132 5.2

L/XL comes with Maxxis Minion 29x2.5WT tires, S/M comes with a Maxxis Minion 29x2.5WT front tire and a 27.5x2.5WT rear tire.

Sizing Guide (Rider Height)

s
152–165CM5'0"–5' 4"
m
163–175CM5'3"–5' 8"
l
173–185CM5'7"-6'1"
xl
183–198CM6'–6'5"
Frame Material Carbon Fiber
Wheel Size 29” up to 2.5" tires on L/XL, 27.5" up to 2.6" on S/M
Front Travel 170mm forks (Max 190mm)
Rear Travel 155mm
Boost Axles 148mm rear / 110mm front
Seatpost Diameter 31.6mm
Rear Brake 203mm post mount / 220mm max
Chainstay Length S/M 439mm, L/XL 444mm
Bottom Bracket NA
Chainline 55mm chainline, 182mm Q Factor
Chainguide Compatible with Bosch Smart System Chain Guides (M/L/XL), Gen 4 (S)
Headset ZS44 upper / ZS56 lower
Colors Forrest Service Green or Storm Blue
Sizes S / M / L / XL
Frame Warranty 7 years
Electronics Warranty 2 Years
Motor Bosch Performance Line CX
Battery Bosch 750 Wh Powertube (M/L/XL), 625 Wh Powertube (S)
Charger Bosch Smart System Charger
Display Bosch Kiox 300
Oso specs green 28927
Oso specs blue 28927
Empty Name 1
Empty Name 2
Oso specs green 28927
Oso specs blue 28927
Empty Name 1
Empty Name 2

Oso Specific FAQs

All our manuals are available here.

Tel: 1-833-BOSCH-EB (267-2432) or at their website here.

The Oso has a Bosch Performance Line CX Motor. Sizes medium through XL utilizes a 750 Wh Powertube battery. The Oso is charged via the Bosch Smart System Charger.


The size small utilizes a BES2/GEN4 Bosch Motor & 625 Wh Powertube battery.

It takes six hours to fully charge the battery and just over two hours for a 50% charge.

Yes, but the bike is optimized around a 44 mm offset fork. The 51 mm-offset fork shortens the trail (the distance between the contact patch and the steering axis), which can cause the front end to feel less stable. We prefer it with a 42-48 mm offset fork, but the choice is yours.

The Oso is compatible with the Fox X2, Fox DHX2 Coil (MY21 and newer), Fox DPX2 (MY18 and newer), and öhlins TTX Air. It is not compatible with the Fox Float X, DHX, Rockshox, DVO, or Cane Creek products.

When attempting to install a shock not on the approved list, please deflate the shock and cycle through the entire stroke to verify clearance.

Yes, installing a 205x65mm trunnion shock provides 170mm of rear travel. We recommend pairing this with a 190mm Rockshox Zeb, a 190mm Fox 40 (with 48mm offset crowns), or a 180mm Fox 38.

No. The hydraulic hose's diameter is too large for the frame's internal cable tunnels. However, the Reverb AXS is compatible!

The small and medium Oso ship with a 27.5” rear wheel. The large and extra-large use a different 29” specific rear triangle. We do not recommend installing a 27.5” wheel on the large and extra-large sizes as it lowers the bottom bracket height.

No, currently we do not offer 27.5" or 29" swing arm kits aftermarket.

The Oso is designed to accommodate tires up to 2.5” wide. We recommend double-checking fitment before riding.

The largest chainring you can install on the Oso is a round 38T. We recommend the stock 32T chainring. This allows you to climb very steep terrain. When shifted into the hardest gear (32x10), the bike spins out at 25 mph. The motor does not assist the rider over 20 mph or 25km/h (depending on your home country).

The use of oval chainrings is not approved by Bosch as they can cause issues with the drive unit.

The Oso fits a 26 oz Purist water bottle on medium, large and extra large frames. The size small frame is compatible with an Abloc Arrive S (550ml/18.5oz), Specialized Big Mouth (21oz), and Polar Bottle (15oz) when used with an Arundel Side Loader Cage.

Our complete GX build in size Large weighs 53 lbs (24 kg).

General FAQs

To see our general FAQs click here.

Dropper Post Saddle Height Calculations

Do not try to insert your post deeper than these measurements. Forcing the post can result in a seat tube failure.

IMPORTANT: Before riding, check the saddle to tire clearance with the dropper post fully dropped and the air out of the shock with frame compressed to bottom out. Small and Medium minimums are controlled by tire bottom out.

Bike Yoke Revive

Measurement from center BB to center of saddle rail (mm)

Drop Min/Max S M L XL
125 Min 619 616 n/a n/a
  Max 711 732 n/a n/a
160 Min 687 684 688 n/a
  Max 760 781 781 n/a
185 Min n/a 734 737 744
  Max n/a 801 800 815
213 Min n/a n/a 801 808
  Max n/a n/a 864 879

Fox Transfer

Measurement from center BB to center of saddle rail (mm)

Drop Min/Max S M L XL
125 Min 614 612 n/a n/a
  Max 690 712 n/a n/a
150 Min 668 651 655 n/a
  Max 744 765 764 n/a
175 Min n/a 707 710 731
  Max n/a 821 820 835
200 Min n/a n/a 765 772
  Max n/a n/a 875 890
Hardware Torque Spec (Nm) Thread Treatment / Notes
Motor
Motor bolts 20 Loctite 243 if no green threadpatch
Motor cover Guard 2 Grease
Motor Bash Guard 2 Grease
Downtube Bash Guard 2 Grease
Upper Battery Mount 12 Grease
Lower Battery Mount 12 Loctite 243 if no green threadpatch
Speed Sensor Cable Clip 2 Grease
Charge Port Exterior Bolts Barely Tight/Just Touching Dry
Battery Door Cover Quarter turn: left to release, right to latch None
Suspension
Forward Shock Mount Bolts 12 Inside of the trunnion mount threads should be treated with Loctite 243 (if no green threadpatch on bolt)
Rear Shock Bolt 10 Titanium Bolts: Ti anti-seize on shaft and threads
Linkage
Top Upper Link Bolt 20 Loctite 243 on threads (if no green threadpatch), grease on flange
Bottom Upper Link Bolt 20 Loctite 243 on threads (if no green threadpatch), grease on flange
Lower Link 6mm Side Preload Bolts 3 Loctite 243 on threads (if no green threadpatch), grease on flange
Lower Link 5mm Pinch Bolts 8 Loctite 243
Misc
Rear Brake Caliper 6 Loctite 243
Seat Binder 7 Grease
Derailleur Hanger Bolt 25 Dry (reverse thread!)
Rear Axle 12 Grease