Otso Arctodus


Financing Available on Bikes + Accessories: Financeit


If you want one you must act fast! Extremely limited stock Canada wide!

Product total
Options total
Grand total

Fat Bike Guarantees

Need a little help? We know that finding the right fat bike can be hard. Give us a call at 844-464-2453, or send us an email at eh@fatbikes.ca for pro advice!

Otso Arctodus

Big adventures require a bike that can rise to the occasion. Arctodus is named after Arctodus simus, an Ice Age behemoth that was the largest bear to ever walk the Earth. Like its namesake, Arctodus the bike is versatile, strong, and ready to explore. It has adjustable geometry, a durable steel frame, a massive front triangle for a frame bag, lots of cargo mounts, and can clear the biggest fat bike tires on the market. Arctodus is ready for afternoon exploration, polar expeditions, and everything in between.

We have customized the Arctodus to have PURPLE seatpost clamps, headsets, headset spacers, and bolts from Wolf Tooth for that extra splash of colour to match the OTSO logo on the downtube.


Arctodus was built around a 26″ x 4.8″ tire for optimal handling and control on loose trails. It can fit the biggest fat bike tires in the world. The biggest fat tire on the market is 26″ x 5.05″ and Arctodus eats them like a snack with room to spare. Same as 27.5″ x 4.5″, which is the biggest 27.5″ tire available. Arctodus is the only bike to clear tires this big with a 12-speed drivetrain without chain interference. This is a bike that prays for snow and cuts its own trail.


A key feature in all Otso bikes is adjustable geometry and the ability to adapt the bike for the ride ahead. The patented Tuning Chip rear dropout system can change wheelbase length by up to 20mm, raise or lower the bottom bracket height by up to 4mm, and change the head tube angle by +/- 0.5º. Use the rear position when the trails are loose and you need as much control as you can get. Use the front position when the snow is firm and the trails let you take turns with a little speed. No matter the conditions, Arctodus has an answer.


There’s no need to wait for the trail groomer. Arctodus was made for foot trails, forest paths, and snow-covered frozen lakes. The bombproof steel frame can withstand the demands of an expedition. A large front triangle can fit a healthy full frame bag. The carbon fork has mounts on either side for cargo. A rear rack can be attached via mounts on the seat stays. Even the geometry is catered for exploration, with extra trail for optimal flotation and bottom bracket height that’s friendly with deep snow. Whether you’re exploring local trails or a national forest, you can trust Arctodus to keep you riding.

Build Kit

Frame Chromoly with Tuning Chip™ dropout system
Fork Lithic carbon fat fork, suspension corrected, tapered steerer tube, 485mm axle-to-crown, 51mm offset
Headset Wolf Tooth Performance Headset, ZS44/EC44
Rear derailleur Shimano SLX M7100, 12-speed
Front derailleur None, 1x only bike
Shifters Shimano SLX M7100 Trigger, 12-speed
Cassette Shimano SLX M7100, 10-51t, 12-speed
Brakes Magura MT4
Cranks Race Face Aeffect with Wolf Tooth CAMO System P2 (+4mm offset) spider, 30T chainring
Bottom bracket Race Face, BSA 100mm
Handlebar Race Face Ride, 740mm riser
Grips Wolf Tooth grips
Stem Aluminum
Seatpost Aluminum, 31.6mm
Seat WTB Volt Medium, 142mm width
Wheels Lithic Rhyolite 90 26″ 84mm with Lithic Hubs
Tires Terrene Johnny 5 Light 26″x4.8″
Chain Shimano SLX 12-speed
Frame Sizes S, M, L, XL

*Builds are subject to slight changes based on availability. Customers will be notified

*Assembly Required

Upgrade Options

Tires – We have the largest selection of Fat Bike Tires in Canada and know the best to spec for each type of rider and condition. Our on-site trail system allows us to test each tire on multiple rims and pressures right out our door in a variety of snow conditions (We’re located in the Snow Belt!). We offer tires from Terrene, 45NRTH, Maxxis, and Surly.

Brakes – Not every rider prefers the brake spec of every stock build so if you want better stopping power out of the box on your build we offer a good selection of brake upgrades from SRAM, Shimano and Hope to swap into your bike build.

Wheelsets – Custom fat bike wheels are our specialty and 100’s of sets have run through our local wheel builders hands. On any build you can opt for a custom wheelset from our selection of rims from Foundation (our in house carbon), HED, Lithic, Stan’s and hubs from Hope, DT Swiss, Onyx and Industry Nine.

Cockpit – Personalizing your build comes down to the cockpit and ensuring it fits you best. These are your touch points and also a great way to personalize your ride. We offer a large selection and colors in handlebars, stems, seatposts (dropper options), saddles, grips and right down to the pedals. Why settle for off the shelf when you can have your bike built the way you want it with parts from your authorized dealer for Raceface, Chromag, PNW, OneUp and many more!

Bags & Racking – We also offer a wide selection of racks and bike packing accessories from EVOC, Salsa, Relevate Designs, PRO and More with special order color and custom frame bag options!

Give us a call for details.

Frame Size Small Medium Large X-Large
Recommended rider height 4’9″-5’5″ 5’5″-5’9″ 5’9″-6’1″ 6’1″-6’7″
Recommended rider inseam 29″-32″ 31″-33″ 32″-35″ 34″-37″
Effective top tube 589mm 610mm 632mm 657mm
Nominal head tube angle 68.5° 68.5° 68.5° 68.5°
Tuning Chip induced head/seat tube angle change ±0.2° ±0.2° ±0.2° ±0.2°
Head tube length 90mm 90mm 100mm 120mm
Nominal seat tube angle 74° 74° 74° 74°
Seat tube length 380mm 420mm 465mm 510mm
Bottom bracket drop 80mm 80mm 80mm 80mm
Chainstay length 440-460mm 440-460mm 440-460mm 440-460mm
Wheelbase 1119-1139mm 1140-1160mm 1162-1182mm 1189-1209mm
Trail 94mm 94mm 94mm 94mm
Fork offset 51mm 51mm 51mm 51mm
Rigid fork axle to crown length 485mm 485mm 485mm 485mm
Stack 607mm 607mm 617mm 635mm
Reach 415mm 435mm 455mm 475mm
Standover 707mm 736mm 773mm 810mm

1 Step 1

Contact Us To Discuss A Build

Nameyour full name
Messagewhat are you inquiring about?
0 / 500


Bikepacking.com introduction:

Introducing the Otso Cycles Arctodus


S, M, L


There are no reviews yet.

Be the first to review “Otso Arctodus”

Your email address will not be published. Required fields are marked *