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2020 Thesis

The OB1 — 650b

A carbon frame gravel bike with upper mid-range components and sram rival hydraulic disc brakes.
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Manufacturer Price

$3,299
FrameCarbon
SuspensionRigid
ForkCarbon
Wheels650b Carbon
Drivetrain1 × 11
GroupsetRival
BrakesSRAM Rival Hydraulic Disc
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Insights
Ride Feel

Based on frame geometry and build specs.

Rider Position
relaxedaggressive
Terrain
smoothrugged
The OB1 — 650b
Other Gravel bikes
Sizing
XS

5'0" – 5'5"

SM

5'4" – 5'8"

MD

5'5" – 5'11"

LG

5'10" – 6'3"

XL

6'0" – 6'6"

Rider Fit Notes

None yet.

Do you have this bike? Help other riders make a decision about which size will work for them by sharing your own size and fit notes.

Reviews
Bikerumor
Thesis rolls out OB1 gravel frameset module + RidersClub for crash replacement at cost

Oct 2020 · Zach Overholt

One of the most affordable carbon gravel bikes just got even more attractive with the option of buying a frameset module to DIY the build.

Read Review

Cycling Tips
Thesis OB1 long-term review: Good performance, lots of custom options - CyclingTips

Aug 2019 · James Huang

The Thesis OB1 isn’t flashy, and the upstart brand name carries no prestige. It’s not particularly light, it definitely isn’t aero, and in fact, there’s not a ton about it on paper that will blow anyone’s doors off in general. But it’s a very good bike nonetheless, and wonderfully versatile in terms of what you […]

Highs
  • Good geometry, great spec, outstanding value

Lows
  • Average frame, value equation is region-dependent

Read Review

CX Magazine
Bike Review: Thesis OB1 Carbon All-Road Bike

Apr 2019 · Clifford Lee

The Thesis OB1 is a carbon all-road bike that fits wide 650b and skinny 700c tires. Is it ready to do it all and help reduce the number of bikes you need?

Read Review

Geometry
Specs
Build
Frame

Thesis OB1 Carbon

Fork

Thesis OB1 Carbon with SteerSafe

Bottom Bracket

Thesis 2-Piece Aluminum Interlocking

Headset

Thesis Oversized Integrated

Stem

Thesis Ultralight

Handlebar

Thesis Compact Ergo Flare

Saddle

Thesis Endurance 148 Saddle

Seatpost

Thesis Ultralight 3D Forged ⸱ 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

TypeRigid

Groupset
Rear Derailleur

SRAM Rival 1 Long Cage Clutched

Crank

Thesis Narrow-Wide Direct Mount Single

Shifters

SRAM Rival 22 Hydraulic

Cassette

SunRace Ultra Wide Range, e*thirteen TRS Plus, SRAM XG-1150

Chain

SRAM PC1110 with Quick Link

Brakes

SRAM Rival 22 Hydraulic

TypeSRAM Rival Hydraulic Disc

Wheels
Rims

Thesis Ultra-Wide Carbon 650B ⸱ 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 ⸱ 370g +/- 5%

Spokes

Pillar PSR X-TRA 1420 Cold-Forged Bladed

Front Hub

DT Swiss DT350

Rear Hub

DT Swiss DT350

Tires

WTB 650B Venture ⸱ WTB Venture 650B x 47mm (555g) ⸱ Supple tanwall casings ⸱ Tubeless

Disc Rotors

SRAM Centerline Centerlock 160mm

Rider Notes
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First added March 2

Last updated March 2

Not listed for 2,279 days