You've got insider access! Our next batch of Thesis OB1 bikes is almost finished and will ship by end of March. Order by 2/23 and you will receive free shipping and a Thesis Skyfade Pro Kit with your order!
Our original legendary all-road gravel bike. With a crisply shifting SRAM Rival 1x drivetrain, hydraulic brakes, and wide range cassette, the OB1 is equipped to handle the steepest pitches you point it up, or down. With our robust yet trim carbon wheelset and premium aluminum cockpit components, you get a parts spec that won’t let you down or leave you wanting.
Chase down roadies, explore some new singletrack, or load up for a long adventure. Join the N=1 revolution.
Current lead time: 4-6 weeks
Weight: ~18.5 lbs (size M, standard seatpost)
Arrives 85% assembled (see prep guide)
Why you'll love the OB1
- Endurance road geometry for all day comfort and balanced handling.
- Bombproof carbon wheels built for speed, strength, and durability at a race-ready weight. Choose between 650Bs and 700Cs, or swap 'em in 90 seconds.
- Tubeless done right with high-volume tires matched to wide rims for easy set-up, fewer flats, greater efficiency, and an extra smooth ride.
- Tailored fit with customizable choice of stem length, bar width, and crank length.
Gearing for every adventure
- 1x11 drivetrain allows crisp simple shifting with no cross-chaining, chain slap, or chain drop, with a cage-lock feature on the rear derailleur that makes it super easy to swap wheels or fix a flat.
- Slickly integrated dropper post using your left shifter puts you in control when the going gets rough.
- Thesis Hollow-Forged Cranks offer incredible stiffness and durability.
- Ride-specific gearing with your choice of chainring and cassette.
Obsessive on the details
- A creak-free bottom bracket with oversized Japanese stainless steel bearings and a 2-piece aluminum shell that threads together for perfect alignment.
- Shock-absorbing bar tape and a remarkably comfortable saddle for all day riding.
- Mounting points galore for bags, extra bottles, fenders, bento, and any other gear you need for your all-day (or all-month) adventure.
Click on the name of each component to learn more about why we chose it. Every detail, down to the bolts and bearings, is selected for the optimal balance of performance, durability, and serviceability.
To learn more about our approach, check out how we built a high-end carbon dream bike.
DETAILS- Endurance road geometry
- Clearance for 650B x 47mm or 700C x 40mm tires
- Discreet mounting points for: (5) bottle cages, racks, bento, and clip-on accessories
- Clean internal routing for hoses and full cable housings, with foam sleeves sheathing for sound dampening
- Round, dropper-ready 27.2 seat tube
- Accommodates up to 46T single or 50/34T double chainrings
- Reinforced Toray 800/700 blend carbon construction
- Fiberglass anti-corrosive layer at seatpost, bottom bracket, and headset interfaces
- 1145g +/-5% (medium, black finish, frame w/o hardware)
Choice of: XS, S, M, L, XL (See Geometry)
WHY WE CHOSE ITFrom road to gravel to travel, our OB1 frameset is ready for every road. Its sleek road-bike design hides clearance for wide dirt tires and discreet mounting points for bags, fenders, racks, extra bottles, and everything else the ride demands. From reinforcement at every hole and boss, to anti-corrosive fiberglass where carbon meets metal, to bolt-secured aluminum cable guides, we've invested in the details to deliver you performance without compromise.
DETAILS- Steersafe-reinforced carbon steerer
- Clearance for 650b x 47mm | 700c x 40mm tires
- Accommodations for fenders, headlight, light, and bottle cages
- 12x100mm thru-axle dropouts
- Reinforced Toray 800/700 carbon construction
- 495g total with SteerSafe installed
WHY WE CHOSE ITWe created SteerSafe to ensure your carbon steerer is fully supported against stem clamping forces. SteerSafe is an aluminum tube with built-in starnut that gets bonded into our carbon steerers at the factory. To shorten a SteerSafe equipped steerer, simply cut through the carbon and aluminum layers using a guide and a carbon-specific blade as you would a normal carbon steerer, then use ultra-fine sandpaper to create a smooth, slightly rounded edge. Finish by torquing the lubricated stem bolts to 5 Nm.
DETAILS- Hollow bolt-on with 6mm hex head
- 12mm front | rear
- Thread length and pitch matched to OB1 frame/fork
- Machined 7075 aluminum
- 82g +/- 5% per set
WHY WE CHOSE ITEach thru-axle is machined from a single billet of ultra-premium 7075 aluminum. With a built-in washer for smooth installation, our bolt-on thru-axles offer stiffness, security, and easy wheel removal without the extra ~100g of weight of levered designs and uses a 6mm hex wrench.
DETAILS- Standard interface for even clamping
- Steel bolt & threaded insert for trouble-free adjustment
- Machined 7075 aluminum
- 20g +/-5%
WHY WE CHOSE ITOB1's seat clamp achieves its integrated look while utilizing a traditional clamping interface that, unlike many proprietary integrated designs, evenly distributes clamping forces. This helps prevent damage to frame or post, post slippage, or post binding (dropper post). We finish it off with a lubricated nut and bolt for a lifetime of trouble-free use. Be sure to coat your seat post with grip paste before installing.
DETAILS- Oversized 1-1/2" stainless steel angular contact lower bearing
- Standard 1 1/8" angular contact upper bearing
- Sealed upper cap
- Replaceable aluminum split crown race
WHY WE CHOSE ITSelected for durability, OB1's extra large 1-1/2” angular contact lower cartridge bearing distributes the extreme loads this component experiences over more and larger balls. The sealed top cap provides an extra barrier to water penetration and its replaceable aluminum split crown race protects the carbon steerer crown from wear while being less prone to creaking than non-split races. While it adds a handful of grams relative to smaller diameter options, we don't believe in shedding weight at the expense of durability.
DETAILS- 1-bolt replaceable
- Stiff for use with long-cage derailleurs
- Axle threads directly into the hanger
- Extra included just in case
WHY WE CHOSE ITFlexy derailleur hangers compromise shifting and are quick to fail. OB1's is stiff and strong to withstand the greater loads placed on it by today's long-cage derailleurs and wide range cassettes, but will still sacrifice itself to protect the derailleur and frame in the event of a major impact. And don't worry - we include an extra just in case. Mounting points for all your gear:
- 2 bottle mounts in the front triangle
- 1 bottle mount below the downtube
- 1 bento mount on the top tube
- 2 bottle mounts on the fork blades
- Front and rear fender mounts (seat stay bridge included)
- Wide central clamping area on handlebar
Note: For optimum performance, load your heaviest items in a frame bag secured in the main triangle.
Max weight of rider + gear: 115kg (254lb)
DETAILS- 116mm drop | 75mm reach | 10 ° flare
- Comfy flat top sections
- Wide 100-180mm x 31.8mm clamp area
- Double butted 6061 aluminum
Choice of: 360, 380, 400, 420, 440mm widths (center-to-center at the hoods)
WHY WE CHOSE ITAero on the tops, control and comfort in the drops. With a short reach, shallow drop, and subtle 10° of flare, our handlebar keeps you narrow when motoring on the hoods while offering greater leverage when cornering, descending, or shredding dirt in the drops, all while reducing back and wrist strain. Its wide central clamping area allows you to attach a bell, GPS, bar bag, aero clip-ons, or all 4 at once if that's what your adventure requires.
DETAILS- 3D forged 7050 aluminum
- 7° angle
- 105g (100mm)
Choice of: 70, 80, 90, 100, 110, 120 mm lengths
WHY WE CHOSE ITA top-of-the-line stem equivalent to others retailing at $100 or more, our 7050-series aluminum stem is strong and stiff yet lighter than others' $250+ carbon stems.
DETAILS- 148 width
- 244 length
- Wide, supportive nose
- Pressure relieving padding and cutout
- Hollow Cr-Mo rails
- 261g +/- 5%
WHY WE CHOSE ITWide, short, cut-out saddles like this one first gained popularity among triathletes and time-trialists looking for improved comfort over long stints in extremely aggressive positions. Eventually roadies and mountain bikers discovered their benefits and brought them into their disciplines as well. With a bit more cushion for mixed terrain riding and hollow Cr-Mo rails for outstanding strength, this is a saddle meant for long days on rough roads.
We spec our Endurance 148 saddle across our entire line of bikes. Our riders love it so much that many have outfitted their entire stable with them.
DRIVETRAIN & BRAKING
- Direct mount for stiffness, weight, & easy swapping
- Long-wearing 7075 aluminum
- Standard SRAM-type 3-bolt interface | 6mm offset
- 99g +/-5% (42T)
Choice of: 38, 40, 42, 44, and 46 tooth options
WHY WE CHOSE ITMachined from a single plate of long wearing 7075-series aluminum to eliminate every unnecessary gram, our chainrings feature contoured narrow-wide teeth for smooth, drop-free operation and direct-mount interfaces for a stiffer and lighter overall system.
DETAILSSunRace Ultra Wide Range
- 11-42T offers a wide 382% range with smaller jumps
- 11-46T offers an even wider 418% range with more low-end
- 404g +/-5% (11-42T) | 465g +/-5% (11-46T)
- Note: 11-46T requires use of included spacer
- 10-42T offers a very wide 420% gear range
- 397g +/-5%
- Note: Requires the use of SRAM XD or XDR freehub (included with casssette upgrade)
e*thirteen TRS Plus
- 9-39T offers wide gear range of 433% with minimal weight penalty
- 9-42T offers an extremely wide 467% gear range
- 9-46T offers the widest gearing range available with 511%
- 315g +/-5% (9-39T) | 330g +/-5% (9-42T) | 395g +/-5% (9-46T)
- Note: Requires the use of SRAM XD or XDR freehub (included with casssette upgrade)
WHY WE CHOSE ITSlick-shifting, and durable, we've been rocking 1x11 drivetrains using these premium SunRace cassettes for years to great effect. With proper chain maintenance, you'll get thousands of miles of trouble-free use before needing a replacement.
With a bump in top end gear range and excellent wear properties the SRAM XG-1150 pairs perfectly with a second wheelset to deliver the gearing you need when out on the road.
Immense gear range without a weight penalty makes the e*thirteen TRS Plus range an excellent choice for a number of use cases. The 9-39T offers substantial range and reasonable gear jumps, with a top end bailout gear that won't spin out chasing a fast group ride on the road. The 9-46T has even greater range than our AXS 1x Eagle build kit, while remaining relatively trim, making it well suited to carrying a load while bikepacking when paired with a smaller chainring. e*thirteen's 9-42T is the Goldilocks of gravel gearing: just right.
DETAILS- Clutched to prevent chain slap or drop
- Cage-lock for exceptionally easy wheel removal/swapping
- Long-wearing cartridge bearing pulleys
WHY WE CHOSE ITFunctionally identical to Force 1 except for its aluminum vs. carbon front cage plate (~8g), SRAM's Rival 1 long cage rear derailleur features worthwhile upgrades over Apex 1 that include more durable cartridge bearing pulleys and a 50g+ lighter weight. It's clutched main pivot prevents chain slap and drops when charging through rough terrain, and its clever cage-lock feature makes swapping between wheelsets a breeze.
DETAILS- Hydraulic braking
- Flat-mount dual piston calipers
- Adjustable reach
- All OB1s come with front and rear shifters
WHY WE CHOSE ITSRAM uses the same internals across all its road lines to achieve identical pro-level shifting and braking performance. With the only relevant differences being weight and finishes, we skipped Force's carbon levers (42g difference) and invested in high-end carbon wheels, lightweight cockpit components and other performance. durability, and serviceability upgrades while saving vastly more weight. While Rival and Apex are identical except for finishes, we went with the former due to its availability with a front shifter to allow easy addition of a dropper post or front derailleur.
DETAILS- Stiff, hollow box-section arms
- Lightweight & tough 7075 aluminum
- Wide-stance BB386 spindle (30 x 86.5mm)
- SRAM-type 3-bolt direct mount chainring interface
- 1-bolt removable drive-side arm
- Compatible with 4iiii power meters
- 625 grams (172.5mm)
Choice of: 155, 160, 165, 170, 172.5, 175mm
WHY WE CHOSE ITStrong, Stiff, Light: Pick 3. How do you create a crank that achieves extraordinary stiffness-to-weight in an easily serviceable package that isn't afraid of a rock strike? Take two billets of ultra premium 7075 aluminum. Smash each under 600 tones of force to form two hollow, box-section arms. Then take another billet of that same alloy and machine it into a large diameter BB386 spindle to push the bottom bracket's oversized bearings as far apart as possible for even more stiffness and durability. Sandblast rather than polish all surfaces to pound-out microfractures, machine out required interfaces, and anodize everything for an even harder and longer-wearing finish. On the non-drive side, press the spindle directly into the arm to reduce weight. On the drive side, use a single oversized bolt to cinch the burly spline interfaces of the arm and spindle together for easy crank removal and chainring swapping.
DETAILS- Precision-milled, thread-together aluminum shell
- Premium NSK Japan 6806 stainless steel sealed cartridge bearings
- Built to the open BB386EVO standard
Note: Uses SRAM DUB 29mm spindle adaptors where appropriate.
WHY WE CHOSE ITOur precision-milled, thread-together aluminum shell is strong and stiff to ensure perfect alignment and support our widely-spaced, large-ball cartridge bearings. It's the same $70+ solution that mechanics turn to when the cheap, plastic press fit bottom brackets creak and fail. It adds quite a bit of cost and a handful of grams, but we think the increased durability, efficiency-under-load, and general peace of mind are well worth the investment.
DETAILS- 114 link
- Quick master-link
WHY WE CHOSE ITThis chain gets the job done with neither fanfare nor fuss. Designed by SRAM to work with all their 1x11 drivetrains, the workhorse PC1110 shifts and wears as well as far more expensive models. Keep it clean, treat it regularly with a wax-based lube, and replace it the moment your checking tool (you do have one, right?) indicates elongation in order to keep your drivetrain quiet, your shifts snappy, and your relatively expensive chainrings and cassettes free of premature wear.
DETAILS- Stainless steel
- 160mm front | rear
WHY WE CHOSE ITSRAM's Centerline 160mm rotors offer a blend of power, modulation, smooth operation, and heat-management. We chose a Centerlock interface for easier installation and removal.
Want to use your own drivetrain? Check out our Bring Your Own Drivetrain option.
DETAILS- Famously bombproof 18t "Star Ratchet"
- (4) premium 6902 sealed, large-ball cartridge bearings
- Centerlock rotor interfaces for easy rotor removal/installation when travelling
- 28 hole J-bend flanges
- 12 x 142mm thru-axle (convertible to other standards)
- Shimano Road or SRAM XDR freehub with spacer for Shimano Road or SRAM XD
WHY WE CHOSE ITExtreme loads and environmental stresses make rear hubs notoriously prone to failure. That's why we invested in DT Swiss's rightfully venerated DT350 rear hub. It features the famously strong and durable Star Ratchet engagement system, large 6902 sealed cartridge bearings, tool-less serviceability and convertibility to other axle or freehub standards, and a centerlock interface for easy rotor installation and removal.
This hub is twice as strong and 3-5x more expensive than the traditional pawl-based models some brands employ to reduce cost, and weighs only a few grams more than the under-built models often employed to achieve attention grabbing weights at the expense of durability.
We've reviewed the testing data, talked to mechanics, and have been abusing DT Star Ratchet hubs ourselves for over 15 years. Whether you're ripping it up on singletrack, touring through some remote wilderness, or simply putting in long miles year after year, these are the hubs you'll want to trust to keep you going.
You can learn more about DT's Star Ratchet engagement system here.
DETAILS- (2) premium 6802 sealed cartridge bearings
- Centerlock rotor interface
- 28h J-bend flanges
- 12 x 100mm thru-axle
- 136g +/- 5%
WHY WE CHOSE ITDT350 front hubs are famously durable, serviceable, and adaptable. They also achieve their light weight without resorting to durability-compromising tricks. What do we mean? Just as there are brands that will use failure-prone aluminum nipples to shave grams, there are others who may spec a hub with tiny bearings and a narrow hub shell to achieve an eye-catching weight. However, those small bearings wear out fast, and that narrow shell may not withstand the torsional loads associated with disc brakes.
DETAILS- Cold forged
- Aero bladed
- Sandvik T302+ stainless (Sweden)
- Single length
- 4.3g each
WHY WE CHOSE ITWhy invest so much on so many fancy bladed spokes? Because the same cold-forging process that turns a length of round straight-gauge wire into a light and aero bladed spoke also improves strength-to-weight and elastication by realigning the grain flow of the metal and reducing its cross-sectional area. The result is a spoke that can be run at high tension while experiencing less change in tension and thus fatigue with each wheel rotation or impact. Furthermore, unlike cheaper round "butted" spokes that are in fact cold-forged in a similar process, bladed spokes can easily be built into a wheel and later trued without inducing spoke wind-up, further extending the life of the wheel. To cap it off, we went with a single length of J-Bend spoke to make it easier to find should one fail, and avoided low spoke counts to make it unlikely one ever will.
DETAILS- Durable brass
- Resist seizing, splitting, & other failure modes
- Can be trued with tires and rim-tape in place
- 1g each
WHY WE CHOSE ITWhy do mechanics love externally adjustable brass nipples? Aluminum nipples are a trick used by some brands achieve attention-grabbing weights at the expense of durability and serviceability. Aluminum oxidizes and is much softer than brass, making aluminum nipples notoriously prone to seizure, splitting, and failure. The result is that a simple wheel true can turn into a costly rebuild with new nipples and spokes. Weight savings? Less than 18 grams per wheel.
As for the hidden nipples used by some uber expensive brands, no one envies having to remove your tires, sealant, rim tape, and valve stems just to perform necessary maintenance. Aerodynamic advantage? Zero. Zilch. Nada.
DETAILS- Each wheel is built by a single, skilled professional
- 2-cross lacing for lateral and rotational strength
- 28 spokes for durability and stiffness
WHY WE CHOSE ITStrong, durable wheels require more than the best components. That's why we invested having our wheels professionally hand-built and machine checked. With a professional touch-up at 1200 miles and regular check-ups for tension and true, our wheels will continue to perform year after year.
Need help finding the right size? Check out our sizing guide.
All figures in millimeters unless otherwise indicated.
What they're saying about the OB1
"I've been playing bikes for over twenty years now. This bike inspires a mix of speed, fun and confidence I've never felt before. I had high expectations for this bike, and I’m happy to say it has blown me away." - Rachel C.
“I've been loving my OB1. It's opened up a whole other world of riding for me with many new places to explore. Every time I'm on a new trail, I'm blown away by the beauty of the new places I'm discovering, excited to go out and try a route I've never done before and very thankful I have the OB1 to take me to all these places I previously couldn't go to before.” - Andy W.
Find your perfect ride
|The OB1||The OB1 AXS 1x||The OB1 AXS 2x|
|The Gist||Our legendary original OB1, with 1x11 mechanical shifting.||The best of the original OB1, with 1x12 electronic shifting.||The best of the original OB1, with 2x12 electronic shifting.|
|Dropper Post (+$149)||Slickly actuated by front shifter||Actuated by separate lever under left hood||Actuated by separate lever under left hood|
|Shifters & Brakes||SRAM Rival 22 Hydraulic||SRAM Force AXS HRD Electronic/Hydraulic||SRAM Force AXS HRD Electronic/Hydraulic|
|Rear Derailleur||SRAM Rival 1 Long Cage Clutched||SRAM X01 AXS Eagle 12spd Electronic||SRAM Force AXS 12spd Electronic|
|Front Derailleur||--||--||SRAM Force eTap AXS Electronic|
|Chain||SRAM PC1110 with quick link||SRAM GX Eagle with quick link||SRAM Force AXS with quick link|
|Rotors||SRAM Centerline Centerlock 160mm||SRAM Centerline XR Centerlock 160mm||SRAM Centerline XR Centerlock 160mm|
Thesis Hollow-Forged AL:
SRAM Force Carbon:
SRAM Force Carbon: