Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x
Waitlist only: The OB1 AXS 1x

Waitlist only: The OB1 AXS 1x

Regular price $4,999.00



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!




Overview                  Specs                  Geometry                  FAQ

The original, reimagined. With a crisply shifting wireless electronic SRAM AXS 1x drivetrain, hydraulic brakes, and wide range X01 Eagle cassette, the OB1 AXS 1x 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 unboxing 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

  • SRAM AXS wireless electronic drivetrain offers crisp light-touch shifting.
  • Long wearing, lightweight and beautiful SRAM Eagle 10-50T cassette gives you a bailout gear for the steepest climbs and loaded bikepacking trips, while maintaining the top end you need to keep pace on a spirited road ride.
  • SRAM X01 AXS clutched derailleur prevents chain drop and chain slap, with a cage-lock feature on the rear derailleur that makes it super easy to swap wheels or fix a flat.

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.




Chassis    |    Cockpit    |    Drivetrain & Braking    |    Wheels

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.


- 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)
From 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.
- 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
We 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.
- 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
Each 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.
- Standard interface for even clamping
- Steel bolt & threaded insert for trouble-free adjustment
- Machined 7075 aluminum
- 20g +/-5%
OB1'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.
- 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
Selected 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.
- 1-bolt replaceable
- Stiff for use with long-cage derailleurs
- Axle threads directly into the hanger
- Extra included just in case
Flexy 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)



- 1-piece 3D forged 2014-T6 aluminum quill
- Micro-adjustable 2-bolt clamp
- Broadly supportive lower clamp
- 0 offset to match OB1's 73° seattube angle
- 230g +/-5% (400mm), 210g +/-5% (350mm)
OB1's seatpost weighs less than some carbon posts yet is safe to use with clamp-on accessories like bikepacking seat bags. Its quill is forged from a single billet of ultra-premium 2014-T6 aluminum for excellent strength to weight. The 2-bolt head and oversized lower clamp plate offer superior saddle security, support, and micro-adjustability.

This seatpost can be shortened using a standard steerer cutting guide and 32TPI hacksaw blade. Just be sure that there's at least 105mm of insertion into the frame (more is better) and that you sand or file the cut edges to round them off and remove burrs.
- Infinitely adjustable
- Lightweight 1-piece forged head and quill
- Secure 2-bolt saddle clamp with broad rail support
- Premium 7075-T651 aluminum construction
- Clean internally-routed design
- Serviceable with readily available parts
- Tests to an ISO MTB standard
- Actuated by an independent lever
- 405L|110mm (485g), 360L|90mm (460g), 310L|70mm (425g)

Pro Tip: Choose the longest dropper that fits your frame size and saddle height (see geo chart).
A dropper post is a total game-changer. Dropping the saddle out of the way allows you to shift your center of mass down and back over the rear wheel, keeping your front end light and freeing your legs to act as suspension. The result is increased control, speed, and confidence over steep or aggressive terrain. They're even great for fast road descents. We've been riding droppers on our drop-bar bikes since before it was cool, so whether you're looking to get shreddy off-road or just want to feel safer on that high speed road sweeper, a dropper is an option well worth considering.

Want to learn more? Check out our deep dive.
- 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)
Aero 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.
- 3D forged 7050 aluminum
- 7° angle
- 105g (100mm)

Choice of: 70, 80, 90, 100, 110, 120 mm lengths
A 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.
- 148 width
- 244 length
- Wide, supportive nose
- Pressure relieving padding and cutout
- Hollow Cr-Mo rails
- 261g +/- 5%
Wide, 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.



- 44T

Mixed-terrain riding often requires ultra low gearing, particularly when slogging gear up steep dirt roads. Paired with a 10-50T cassette, a 44T chainring offers a monster 500% range with considerably more low end grunt than most 2x options (including that of our OB1 AXS 2x) for steep dirt climbs while maintaining plenty of top end for high speed road descents.
- Monster 500% range
- 10-50T: 10, 12, 14, 16, 18, 21, 24, 28, 32, 36, 42, 50
- XDR freehub-compatible with included spacer
- 355g
SRAM's XG-1295 cassette is a masterpiece of CNC-milled steel and aluminum. Identical in all but finish to their top-of-the-line XG-1299, it saves a significant 100g relative to SRAM's next lightest option. Sporting 12 speeds and a monster 500% range, you'll always have the right gear for your fitness and terrain.
- AXS wireless electronic
- Cage-lock feature for easy wheel swaps
- Roller bearing clutch eliminates derailleur bounce and chain slap
- 388g with battery
Identical in all but finish to their top-end XX1 AXS offering, SRAM's X01 AXS electronic rear derailleur offers the same slick shifting as the cable-actuated 11spd rear derailleur we use on our original OB1 but in a wireless 12 speed electronic format.
- Wireless 12-speed electronic shifting
- Powerful, easily modulated hydraulic disc braking
- Reach adjust to fit hands of all sizes
- Contact point adjustment to dial where the brake pads bite
- Port on each lever for "Blips"
- 750g (both levers with calipers, batteries, and hoses)
SRAM's Force AXS levers take the excellent shifting and braking we've come to love from the SRAM mechanical levers we spec on the original OB1, but with light-touch wireless electronic shifting and the addition of contact point adjustment to dial how the brake pads bite. They are also functionally identical to the top-of-the-line Red AXS save for a ~15g difference in lever weight.
- 44T chainring
- Lightweight carbon arms
- DUB-standard 29mm spindle

Choice of: 165, 170, 172.5, 175mm
SRAM's Force 1 AXS carbon crankset offers the best combination of light weight, durability, and gearing range of any crankset within SRAM's line. We went with their 44T chainring for an optimal balance of top-end speed and low-end grunt, allowing you to tackle everything from screaming road descents to loaded dirt climbs.
- Precision-milled, thread-together aluminum shell
- Premium NSK Japan 6806 stainless steel sealed cartridge bearings
- Built to the open BB386EVO standard
- 135g

Note: Uses SRAM DUB 29mm spindle adaptors where appropriate.
Our 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.
- Chrome hardened pins
- Anti-friction and anti-corrosion finishes
- Includes quick link
- 244g (114 links)
Chains are a wear item that should be checked, cleaned, lubed, and replaced frequently for optimal performance and to preserve your expensive chainrings, cassettes, and derailleur pulleys. Within SRAM's line, we chose the GX 12-speed chain for its hardened steels and anti-friction/anti-corrosion finishes.
- 160mm front/rear
- Smooth rounded edges
- 131g per wheel
We're huge fans of the smooth-braking SRAM Centerline Centerlock rotors we spec on our original model. For our AXS model, we chose the upgraded XR version for its ~23g per wheel lighter weight.
- Single-port USB charger for SRAM eTAP AXS batteries
An electronic drivetrain won't do you much good without a means to charge it, so we of course include a charger with every bike.

Want to use your own drivetrain? Check out our Bring Your Own Drivetrain option.



Thesis Aero-Wide Carbon 700C Wheels

- 44mm deep | 30mm wide | 22mm internal
- Hybrid U/V aero profile
- Aero-optimized for 28/30mm tires
- Wide enough to support 40mm+ tires
- Tubeless-ready mid-hook design (compatible with tubed tires)
- 2.5mm offset, angle drilling, & reinforced nipple seat
- Toray 800/700 blend
- Max pressure 90psi
- 430g +/- 5%
An all-arounder that's optimized for 28/30mm slicks yet wide enough to support 40mm knobbies, our U/V Aero-Wide Carbon rims let you take advantage of the improved rolling resistance and comfort of today's more voluminous tubeless performance tires without sacrificing aerodynamics. They feature  2.5mm of offset, angled spoke hole drilling, and a reinforced nipple seat for high and balanced spoke tensions, which in turn create a stiffer, stronger, and more durable wheelset.  Their tubeless mid-hook design improves impact strength and tire stability at low pressures. With a bias toward speed, these rims are ideal for road, cyclocross, gravel, commuting, and speed touring.
- 700c x 30mm
- Supple tubeless-ready casing
- Slick dual compound tread for efficiency and durability
- 335g
A fast-rolling road slick that isn't afraid of the dirt, WTB's Exposure 30 Road tires employ a supple tubeless-ready casing and a dual-compound tread to offer a great balance of rolling speed and off-pavement capability. Matched to our Aero-Wide Carbon 700C tubeless rims, they're equally suited to all day epics and the the local hammerfest. Run them at 55-90psi depending on weight for optimal performance.

Thesis Ultra-Wide Carbon 650B Wheels

- 650B | 27.4mm internal | 33mm wide | 24.5mm deep
- Optimized for 47mm+ tires
- Tubeless-ready hookless design, also compatible with standard tubed tires
- 3mm offset, angle drilling, & reinforced nipple seat
- Toray 700/800 construction
- 350g +/- 5%
An adventure-lover that's optimized to support popular 47mm gravel tires at low pressures, our Ultra-Wide Carbon 650B rims offer maximumized tire volume for compliance, traction, and stability in the dirt. They feature 3mm of offset, angled spoke hole drilling, and a reinforced nipple seat for high and balanced spoke tensions, which in turn create a stiffer, stronger, and more durable wheelset.  Their hookless design improves impact strength and tire stability at low pressures. With a bias toward comfort and traction, these rims are great for technical gravel, bike-packing, speed commuting, and speed touring.


- WTB Venture 650B x 47mm (555g)
- Supple tanwall casings
- Tubeless
The WTB Venture is the ideal all arounder with pronounced side knobs for cornering grip and a file tread center to keep you rolling fast. It's supple casing and tubeless compatibility give it a smooth ride that holds up in the most challenging conditions. They inflate to around 49mm on our ultra-wide 650B rims and are best at 20-40psi (max) depending on your weight and terrain.
- 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
- 267g
Extreme 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.
- (2) premium 6802 sealed cartridge bearings
- Centerlock rotor interface
-  28h J-bend flanges
- 12 x 100mm thru-axle
- 136g +/- 5%
DT350 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.
- Cold forged
- Aero bladed
- Sandvik T302+ stainless (Sweden)
- J-bend
- Single length
- 4.3g each
Why 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.
- Durable brass
- Resist seizing, splitting, & other failure modes
- Can be trued with tires and rim-tape in place
- 1g each
Why 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.
- Each wheel is built by a single, skilled professional
- 2-cross lacing for lateral and rotational strength
- 28 spokes for durability and stiffness
Strong, 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.


Have a question? Check out our FAQ or reach out to us directly at support@thesis.bike to talk to a real human. We're always happy to talk bikes.

Shop now





Need help finding the right size? Check out our sizing guide.

Frame Size XS S M L XL
Typical Height Range
5'1" - 5'5" 5'4" - 5'8" 5'6" - 5'11" 5'10" - 6'2" 6'1" - 6'5"
A Reach 356 363 378 388 403
B Stack 521 551 571 595 614
C Head Tube 110 138 155 180 200
D Effective Top Tube 515 531 547 570 591
E Wheelbase 987 995 1007 1025 1046
F Front-Center 578 586 598 616 637
G Head Tube Angle 70° 71° 72° 72° 72°
H Fork Offset 51
I Fork Axle to Crown 385
J BB Drop 73
K Chain Stay 420
L Seat Tube Angle 73°
M Seat Tube 440 470 500 530 560
Standover (Midpoint of TT) 720 750 775 805 835
Default Handlebar (C-C) 380 400 420 420 440
Default Stem (7°) 80 90 100 100 110
Default Crankarms 165 165 165 170 175
Default Seatpost 350 350 400 400 400
Dropper Seatpost
Default Length | Travel 315 | 70 360 | 90 360 | 90 405 | 110 405 | 110
Default Saddle Height Range 610 - 660 660 - 735 690 - 750 735 - 820 765 - 850
Alternate Length | Travel 360 | 90 315 | 70 405 | 110 360 | 90 360 | 90
Alternate Saddle Height Range 650 - 705 640 - 690 705 - 790 720 - 795 750 - 825

All figures in millimeters unless otherwise indicated.



What they're saying about the OB1

“LOVE my Thesis. It's really astonishing how fun it is to ride. The 650b wheels make it incredibly fun to shred fire roads and gravel, and the 700c wheels with 30mm tubeless tires are fast and make chip seal feel like glass. You guys have a winner.” - Kelly F.

"My appreciation for the thoughtfulness that went into the bike increases the more I ride it. I love what you guys are doing." - Rich J.




Find your perfect ride

Starting at $3299

Our original legendary all-road gravel bike.

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Starting at $4999

The best of the OB1, now with electronic AXS 1x.

Starting at $5199

The best of the OB1, now with electronic AXS 2x.

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The OB1 The OB1 AXS 1x The OB1 AXS 2x
Starting Price $3,299 $4,999 $5,199
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.
  • Thesis 700C Aero-Wide Carbon
  • Thesis 650B Ultra-Wide Carbon
  • Both wheel packages (+$1199)
  • Thesis 700C Aero-Wide Carbon
  • Thesis 650B Ultra-Wide Carbon
  • Both wheel packages (+$1599)
  • Thesis 700C Aero-Wide Carbon
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
  • SunRace 11-42T (382% range)
  • SunRace 11-46T (418% range)
  • SRAM Eagle XG-1295 10-50T (500% range)
  • SRAM Force XG-1270 10-33T (460% range)
  • Thesis 38T
  • Thesis 40T
  • Thesis 42T
  • Thesis 44T
  • Thesis 46T
  • SRAM 44T
  • SRAM 46/33T
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
Crank Thesis Hollow-Forged AL:
  • 155mm
  • 160mm
  • 165mm
  • 170mm
  • 172.5mm
  • 175mm
SRAM Force Carbon:
  • 165mm
  • 170mm
  • 172.5mm
  • 175mm
SRAM Force Carbon:
  • 165mm
  • 170mm
  • 172.5mm
  • 175mm