Overview
Designed with 3Al-2.5V titanium, this frameset is lightweight, strong, and corrosion-resistant with adjustable geometry, large tires up to 29” x 2.6” or 27.5” x 2.8”, and multiple mounts for gear. The drop bar configuration offers multiple hand positions and aerodynamic benefits, suitable for faster and longer rides on mixed terrain.
| XS | S | M | L | XL | |
| Recommended rider height | 4’10”-5’4″ | 5’3″-5’7″ | 5’7″-5’11” | 5’11”-6’3″ | 6’3″-6’6″ |
| Effective top tube | 547mm | 565mm | 583mm | 600mm | 618mm |
| Nominal head tube angle | 68° | 68° | 68° | 68° | 68° |
| Tuning Chip induced head/seat tube angle change | ±0.2° | ±0.2° | ±0.2° | ±0.2° | ±0.2° |
| Head tube length | 90mm | 100mm | 120mm | 140mm | 160mm |
| Nominal seat tube angle | 75° | 75° | 75° | 75° | 75° |
| Seat tube length | 360mm | 400mm | 450mm | 490mm | 530mm |
| Bottom bracket drop | 68-72mm | 68-72mm | 68-72mm | 68-72mm | 68-72mm |
| Chainstay length | 430-450mm | 430-450mm | 430-450mm | 430-450mm | 430-450mm |
| Wheelbase | 1090-1110mm | 1110-1120mm | 1130-1150mm | 1150-1170mm | 1170-1190mm |
| Trail | 88mm | 88mm | 88mm | 88mm | 88mm |
| Fork offset | 51mm | 51mm | 51mm | 51mm | 51mm |
| Rigid fork axle to crown length | 495mm | 495mm | 495mm | 495mm | 495mm |
| Stack | 595mm | 605mm | 623mm | 642mm | 660mm |
| Reach | 387mm | 403mm | 416mm | 428mm | 441mm |
| Standover | 754mm | 777mm | 810mm | 838mm | 866mm |
Features
Titanium Frame: Made from 3Al-2.5V titanium, providing exceptional strength, lightweight performance, and excellent corrosion resistance.
Adjustable Geometry: The Tuning Chip™ dropout system allows customization of the wheelbase and bottom bracket height, optimizing handling and ride quality across various terrains.
Generous Tire Clearance: Fits tires up to 29” x 2.6” or 27.5” x 2.8”, offering versatility for different riding surfaces and enhancing off-road capabilities.
Versatile Mounting Options: Equipped with multiple mounts for racks, fenders, and gear, making it ideal for bikepacking, long-distance touring, and carrying all necessary equipment for extended adventures.
Drop Bar Configuration: Provides a capable and confident gravel bike setup, perfect for handling mixed terrain with ease, while offering multiple hand positions for comfort and efficiency on long rides.
Specs
Most components can be customized at time of order, contact us!
| DROP BAR | FLAT BAR | |
| Frame | 3Al/2.5V B338 grade 9 titanium | 3Al/2.5V B338 grade 9 titanium |
| Fork | Carbon Lithic Mountain Fork, 15mm thru axle | Carbon Lithic Mountain Fork, 15mm thru axle |
| Headset | Wolf Tooth Performance Headset | Wolf Tooth Performance Headset |
| Rear derailleur | Shimano GRX 822 1x, 12-speed | Shimano SLX M7100, 12-speed |
| Front derailleur | N/A | N/A |
| Shifters | Shimano GRX 600 mechanical, 12-speed | Shimano SLX M7100, 12-speed |
| Cassette | Shimano SLX M7100, 11-51T, 12-speed | Shimano SLX M7100, 10-51T, 12-speed |
| Brakes | Shimano RX400 Hydraulic | Shimano Deore BR-6100 |
| Cranks | Race Face Aeffect, 34T Chainring | Race Face Aeffect, 34T Chainring |
| Handlebar | Lithic Corundum aluminum compact drop with 16° flare | Aluminum, 31.8mm x 780mm, 20mm rise |
| Tape / Grips | Anti-Slip Gel Bar Tape | Wolf Tooth Grips |
| Wheels | DT Swiss M1900 29″ | DT Swiss M1900 29″ |
| Tires | Schwalbe Racing Ralph 29×2.35 Super Ground | Schwalbe Racing Ralph 29×2.35 Super Ground |
| Frame Sizes | XS, S, M, L, XL | XS, S, M, L, XL |
| Bottom bracket standard | Shimano english thread BSA, Ø73mm |
| Maximum chainring size | 1x: 40T round or 38T oval |
| Front derailleur type | N/A |
| Headset | ZS44/28.6 upper, EC44/40.0 lower |
| Seatpost diameter | Ø31.6mm |
| Internal dropper post routing | Yes. Exit port on bottom of seat tube |
| Seatpost clamp | Ø34.9mm |
| Front/rear hub standard | 110x15mm thru axle / 148x12mm thru axle |
| Front/rear axle | Ø15x110mm front, TP=1.5, TL=15mm / Ø12x187mm rear, TP=1.5, TL=12mm |
| Derailleur hanger | Wolf Tooth Tuning Chip Right Dropout |
| Rear brake (rotor) | Flat mount, 74mm post mount available(160mm) |
| Front brake (rotor) | Post mount native, (160mm post mount or 180mm flat mount) |
| Fork axle-to-crown | 490mm (suspension corrected for 100mm suspension fork) |
| Fork offset | 44mm or 52mm |
| Bare frame weight (L) | 3.9lbs (1814g) |
| Fork weight (Enve rigid fork) | 676g |
| Tire clearance (frame) | 2.3″ at 420mm chainstay position, 2.8″ (for 27.5″ wheels) or 2.6″ (for 29″ wheels) at 430/440mm chainstay positions |
| Tire clearance (fork) | Max clearance 29″ x 3.0″ |
| Braze-ons | Three bottle frame mounts, fender, rack, cable clamps, two three-pack mounts on fork |
| Frame Bag Dimensions | X-Small Small Medium Large X-Large |
| Seatpost Insertion Depth | X-Small 180mm; Small 200mm; Medium 250mm; Large 280mm; X-Large 320mm |
| Max weight (rider + gear) | 275 lbs |
| Max spacer stack under stem | 40mm |
| Max spacer stack above stem | 10mm |
| Max stem bolt torque | 6 Nm |
Warranty
Warranty Coverage:
- All Otso frames are warranted against defects in materials and workmanship for 5 years from the date of retail purchase.
- This warranty applies to the original owner only and is not transferable.
- Please keep your sales receipt or order number for any warranty claims to ensure a quick resolution.
What’s Not Covered:
- Damage from improper assembly, maintenance, or user/assembler inexperience.
- Modifications, neglect, misuse, competition, commercial use, or accidents.
- Installation of incompatible components, parts, or accessories.
- Normal wear and tear, or damage to paint, surface finish, or aesthetics.
- Compatibility of original components with a replacement frame is not guaranteed.
- Costs for labor, parts removal, refitting, or re-adjustment, including wheel rebuilds.
Claim Process:
- Warranty claims are limited to the repair or replacement of the defective frame, at Otso’s discretion.
- This warranty does not cover incidental or consequential damages.
Legal Information:
- This warranty gives you specific legal rights, which may vary based on location. It does not affect your statutory rights.