Mountain Frames

The Hoot Ti is a premium titanium hardtail that was designed for bringing the fun to any line on the trail. The frame tubing is the 3Al/2.5V grade 9 titanium that has been an industry favorite for decades. This titanium tubing was selected because it is lightweight, lively, and emphasizes the playful Hoot Ti geometry. The bike features a custom Fox 36 Performance Elite Fork with 140mm of travel to optimize the Hoot Ti ride experience. 3-D titanium printing in the UDH rear dropouts and chainstay yoke pair with short stays for a playful ride. However you choose to ride this titanium hardtail, it’s guaranteed to be a Hoot. PLAYFUL GEOMETRY The geometry of Hoot Ti has one goal: fun. The 425mm chainstays are core to Hoot Ti because they add nimble, playful handling. The 65º head tube and 76º seat tube angles pair for a balanced riding position, while that slack head tube angle, long reach, and low bottom bracket drop of 60mm allow for confident downhill riding on aggressive trails. A shorter standover and lower top tube allow for longer travel dropper posts and more creative, playful riding without the bike getting in the way. Every detail of Hoot Ti contributes to a bike that will bring the party to any trail ride. TITANIUM FRAME The titanium tubing used in the Hoot Ti frame is the 3Al/2.5V grade 9 titanium tubing that has been an industry favorite for decades. This specific frame material was chosen because it is lightweight, lively, and responsive. These are necessary qualities for tubing that need to live up to the playful requirements of the Hoot Ti geometry. 3-D TITANIUM PRINTING The key to bringing Hoot Ti to life. 3-D titanium printing is present in the rear dropouts and the chainstay yoke. Otso engineers leveraged this technology to give Hoot Ti short 425mm chainstays while maintaining the 29” x 2.6” tire clearance. This also allowed for a hidden dropper post routing port behind the BB shell and twin cable clamps that are molded into the chainstay yoke. 3-D titanium printing is also featured at the rear UDH dropouts for a clean look and a brake mount inside the rear triangle. CUSTOM FORK Hoot Ti is built with a custom Fox 36 Performance Elite 140mm travel fork. While any 140mm fork will work with Hoot Ti, Otso engineers worked directly with Fox for this custom option because they wanted the 36mm stanchion of the Fox 36 with the 140mm travel of the Fox 34. This sturdier stanchion is better suited for aggressive, chunky trail riding. The fork features the new Grip X damper, a 44mm offset, bleeders on the fork lower, and black stanchions with black lowers for a stealth look.

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. THE BIGGEST TIRE CLEARANCE 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. When a bike is created for big rides with fresh snow, it needs to fit tires that were designed for the same reason. This is a bike that prays for snow and cuts its own trail. ONE BIKE, THREE WHEELBASE LENGTHS 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 +/.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. DESIGNED FOR EXPLORING 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 frame can be attached via mounts on the seat stays and Tuning Chip hardware. Even the geometry is catered for exploration, with extra trail for optimal flotation and bottom bracket height that will ride above deeper snow. Whether you're exploring local trails or a national forest, you can trust Arctodus to keep you riding. NARROW Q FACTOR Arctodus has a 100mm bottom bracket. This is 30-40mm narrower than other fat bikes that have the same tire clearance. Ride with massive tires without compromising handling. SUSPENSION CORRECT All Otso frames feature suspension-corrected geometry. Arctodus is compatible with suspension forks that have up to 120mm of travel. A few options are available on the Custom Bike Builder. STABILITY & FLOATATION Arctodus geometry was designed for optimal riding on fresh trails. The 68º head tube angle paired with massive tires gives Arctodus more trail than other fat bikes. Even the BB height was selected for clearance in deep snow. DROPPER COMPATIBLE Snowy trails are good with dropper posts, too. A port near the bottom bracket fits a cable and housing for a cable-actuated dropper post.

Voytek changes the fat bike game. It is fast, lightweight, agile, and can handle even the sharpest turns of your local single-track with ease. Think of it as a mountain bike that can fit fat tires with adjustable geometry. We paired a narrow pedal stance-aka Q factor - with aggressive XC race geometry to build a fat bike that can intuitively handle snowy trails like your mountain bike can handle summer single-track without sacrificing ride quality. When the weather turns and the snow turns to dirt, swap out the 26" fat wheelset for a 29" MTB wheelset to keep the party going all year. THE Q-FACTOR IS THE KEY The Voytek has the narrowest Q-factor of any fat bike in the world at 183mm. With a narrow Q-factor, your weight is closer to the centerline of the bike. This is especially important when cornering because it allows for tight, responsive control - the wider Q-factor found on most fat bikes spreads out your pedals and creates a floppy, unstable feel. The Voytek frame was designed around an 83mm bottom bracket, whereas most fat bikes have a bottom bracket north of the 100-110mm range. With the Voytek, you don't need to compromise agile handling to ride up to 4.6" tires. ONE BIKE, THREE WHEELBASE LENGTHS Our Tuning Chip rear dropout is at the heart of the versatile Voytek. With a quick change in positions, the wheelbase of the Voytek can be extended or shortened by up to 20mm, which also changes the bottom bracket height by up to 4mm and the head tube angle by +/.5º. In the forward position, you've got an aggressive, responsive Voytek for your next race. In the rear position, you've got that same intuitive handling but with added stability to make it easier to ride in deep snow or adverse terrain. In the middle, well, that's the best of both worlds. PLUS OR FAT? FAT OR PLUS? We're internally divided here as to whether the Voytek is a plus bike that can handle fat tires or if the Voytek is a fat bike that has the handling worthy of a plus bike. When the trails are packed with snow, we're riding 4" tires. When spring comes and the trails turn to dirt, we swap out tires and ride 29" plus until winter returns. The versatility of the Voytek blurs the lines of plus and fat, keeping the party going all year long. MODERN GEOMETRY Voytek's longer top tube, short chainstays – the shortest in the world for a fat bike – and slightly slacker head tube angle mean more speed and more fun. SUSPENSION CORRECT Voytek's suspension-corrected geometry is compatible with an Otso carbon rigid fork or up to 120 mm travel suspension fork. COMPETITOR TESTED, ISO APPROVED Voytek's patent-pending frame design exceeds all ISO frame safety standards and has been proven over thousands of miles of test riding, including the legendary Iditarod Invitational and Arrowhead 135 competitions. DROPPER COMPATIBLE The EPS molded carbon frame of the Voytek was designed to accept internally routed dropper seat posts.

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. THE BIGGEST TIRE CLEARANCE 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. When a bike is created for big rides with fresh snow, it needs to fit tires that were designed for the same reason. This is a bike that prays for snow and cuts its own trail. ONE BIKE, THREE WHEELBASE LENGTHS 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 +/.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. DESIGNED FOR EXPLORING 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 frame can be attached via mounts on the seat stays and Tuning Chip hardware. Even the geometry is catered for exploration, with extra trail for optimal flotation and bottom bracket height that will ride above deeper snow. Whether you're exploring local trails or a national forest, you can trust Arctodus to keep you riding. NARROW Q FACTOR Arctodus has a 100mm bottom bracket. This is 30-40mm narrower than other fat bikes that have the same tire clearance. Ride with massive tires without compromising handling. SUSPENSION CORRECT All Otso frames feature suspension-corrected geometry. Arctodus is compatible with suspension forks that have up to 120mm of travel. A few options are available on the Custom Bike Builder. STABILITY & FLOTATION Arctodus geometry was designed for optimal riding on fresh trails. The 68º head tube angle paired with massive tires gives Arctodus more trail than other fat bikes. Even the BB height was selected for clearance in deep snow. DROPPER COMPATIBLE Snowy trails are good with dropper posts, too. A port near the bottom bracket fits a cable and housing for a cable-actuated dropper post."

The Ogre can get you to your job during the week, then way out of town on the weekend. It’s not sluggish on pavement or gravel and can also hold its own on singletrack. Ogre brings several sensible features to the 29er platform, including horizontal slotted dropouts with Gnot-Boost spacing, a tweaked non-suspension corrected geometry, and a beefy tire clearance. - 100% Surly Chromoly steel, double-butted main triangle - TIG-welded, Horizontal slotted with derailleur hanger, Gnot-Boost spacing allows the use of 135mm QR hub, 142 x 12mm thru-axle or 148 x 12mm Boost hubs. Features Rohloff torque arm slot and threaded eyelets for fenders, racks and Surly trailer mounts - Full-length Surly Trip Guide housing line guides for derailleurs and brakes; two sets of bottle cage mounts; upper seatstay threaded barrels, mid- and low-blade fully threaded through-blade fork eyelets; threaded holes for racks, fenders and trailer mounting nuts; Rohloff OEM2 axle plate mounting slot - Disc brakes only. Disc mounts are 51mm IS. Note: rear disc brake is limited to 160mm maximum rotor diameter and requires the use of Surly caliper adaptor (included with frames and bikes) - Frame is E.D. coated for increased life expectancy - Tire clearance for 29 x 2.5" or 27.5 x 3"

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. - The Biggest Tire Clearance 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", the biggest 27.5" tire available. Arctodus is the only bike to clear tires this big with a 12-speed drivetrain without chain interference. When a bike is created for big rides with fresh snow, it needs to fit tires that were designed for the same reason. This is a bike that prays for snow and cuts its own trail. - One Bike, Three Wheelbase Lengths 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. - Designed for Exploring 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 frame can be attached via mounts on the seat stays and Tuning Chip hardware. Even the geometry is catered for exploration, with extra trail for optimal flotation and bottom bracket height that will ride above deeper snow. Whether you're exploring local trails or a national forest, you can trust Arctodus to keep you riding. - Narrow Q Factor Arctodus has a 100mm bottom bracket. This is 30-40mm narrower than other fat bikes that have the same tire clearance. Ride with massive tires without compromising handling. - Suspension Correct All Otso frames feature suspension-corrected geometry. Arctodus is compatible with suspension forks that have up to 120mm of travel. A few options are available on the Custom Bike Builder. - Stability and Floatation Arctodus geometry was designed for optimal riding on fresh trails. The 68º head tube angle paired with massive tires gives Arctodus more trail than other fat bikes. Even the BB height was selected for clearance in deep snow. - Dropper Compatible Snowy trails are good with dropper posts, too. A port near the bottom bracket fits a cable and housing for a cable-actuated dropper post.

The same chassis piloted to riotous success in its very first season on the World Cup circuit, the Demo Race frameset brings 27.5/29-inch rear wheel compatibility to the fore in the search for the optimal balance of speed, traction, and maneuverability while allowing for unmatched versatility. Ohlins's TTX 22 M coil shock gives you a head start on suspension perfection, just hang your time-tested race kit before you pick up the search where we left off, and there's a good chance you'll find a few podiums along the way. - The Demo Expert M5 alloy frame is fully optimized to take advantage of the traction benefits of a 29-inch front wheel and the increased maneuverability of a 27.5-inch rear wheel while maintaining the ability to change your rear wheel size to a 29-inch to suit different terrain and riding styles with an adjustable rear end that ensures chainstay length and bottom-bracket height stay dialed no matter the hoop size. - The Ohlins TTX 22 M coil shock is designed to handle the most challenging World Cup Downhill tracks, offering external low-speed compression and rebound adjustment while the Trunnion mount offers extra bushing overlap for increased durability.

Karate Monkey is a highly versatile trail bike that plays the part of 29er and 27.5+ equally well. Karate Monkey delivers a resilient, lively ride on all sorts of gnarly terrain. Its frame is a highly-versatile canvas for whatever dirty masterpiece your brain cooks up. According to our computing machine (Thor) it can be set up in approximately 487 different configurations. Originally designed as a 29er (and the frame that helped spark the 29" wheel movement), the latest Karate Monkey is designed to perform just as admirably as a 27.5+ rig as well. This allows you to pick your poison — provided your poison is having a really great time while permanently donning a huge grin, of course. - Modern trail standards: dropper post compatibility, 44mm headtube, Gnot-Boost rear spacing, thru-axles, suspension corrected fork - Compatibility with most mountain bike standards makes it the perfect parts bin bike (no rim brakes allowed though) - Clearance for 29" x 2.5" or 27.5" x 3" tires

Designed to go where no normal fat bike can, the Surly Moonlander is for riders who want otherworldly capabilities on rocky shorelines, sand, snow, and desolate landscapes not yet discovered. It’s the ultimate choice for explorers who itch for the next great adventure, and aren’t afraid of what they might find. - Constructed from 100% Surly Chromoly Steel for excellent durability - Clearance for 24 x 6.25” tires, as well as 26 x 5.1", 27.5 x 4.8", and 29 x 3" - Comes with rack and fender mounts, as well as accessory mounts on both fork blades to enhance cargo capacity - Four frame sizes to fit most riders: SM, MD, LG, XL