2021 Thesis Bike OB1 Base (650B)

Design
Drop Bar, Rigid, non-suspension corrected
Frame
Carbon/Composite
Fork
Carbon/Composite
Features
Disc brake
Average stack and reachvs category
Somewhat upright stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category

Geometry

XS
S
M
L
XL
Stack
521mm
551mm
571mm
595mm
614mm
Reach
356mm
363mm
378mm
388mm
403mm
Stack to Reach Ratio
1.46:1
1.52:1
1.51:1
1.53:1
1.52:1
Seat Tube Length, C-T
440mm
470mm
500mm
530mm
560mm
Top Tube Length, Effective/Horizontal HT Top
515mm
531mm
547mm
570mm
591mm
Top Tube Slope
11.7deg
11.5deg
10deg
9.2deg
7.9deg
Head Tube Angle
70deg
71deg
72deg
72deg
72deg
Seat Tube Angle
73deg
73deg
73deg
73deg
73deg
Head Tube Length
110mm
138mm
155mm
180mm
200mm
Bottom Bracket Drop
73mm
73mm
73mm
73mm
73mm
Bottom Bracket Height
266mm
266mm
266mm
266mm
266mm
Chainstay Length
420mm
420mm
420mm
420mm
420mm
Chainstay Length Horizontal
413.6mm
413.6mm
413.6mm
413.6mm
413.6mm
Front-Center
578mm
586mm
598mm
616mm
637mm
Front-Center Horizontal
573.4mm
581.4mm
593.4mm
611.4mm
632.4mm
Wheelbase
987mm
995mm
1007mm
1025mm
1046mm
Fork Offset/Rake
51mm
51mm
51mm
51mm
51mm
Fork Length (On-Axis)
385mm
385mm
385mm
385mm
385mm
Trail
69.1mm
high
62.8mm
mid/​neutral
56.5mm
mid/​neutral
56.5mm
mid/​neutral
56.5mm
mid/​neutral
Mechanical Trail
64.9mm
59.4mm
53.8mm
53.8mm
53.8mm
Wheel Flop
22.2mm
19.3mm
16.6mm
16.6mm
16.6mm
Standover Height
720mm
750mm
775mm
805mm
835mm
Tire to Pedal Spindle
84mm
155 mm cranks
87mm
160 mm cranks
94mm
165 mm cranks
107mm
170 mm cranks
123mm
175 mm cranks
Pedal Spindle to Ground Clearance
111mm
155 mm cranks
106mm
160 mm cranks
101mm
165 mm cranks
96mm
170 mm cranks
91mm
175 mm cranks

Base (650B) Build

XS
S
M
L
XL
Wheel Size
650B/27.5
584 mm BSD
650B/27.5
584 mm BSD
650B/27.5
584 mm BSD
650B/27.5
584 mm BSD
650B/27.5
584 mm BSD
Tire Width
47mm
47mm
47mm
47mm
47mm
Tire Width Max
47mm
47mm
47mm
47mm
47mm
Tire Outer Diameter
678mm
678mm
678mm
678mm
678mm
Bike Length with Tires
1665mm
1673mm
1685mm
1703mm
1724mm
Crank Length
155mm
160mm
165mm
170mm
175mm
Handlebar Width
380mm
400mm
420mm
420mm
440mm
Stem Length
80mm
90mm
100mm
100mm
110mm
Stem Angle
7deg
7deg
7deg
7deg
7deg

Published Sizing Recommendations

Height
5 ft 1 in
to
5 ft 5 in
5 ft 4 in
to
5 ft 8 in
5 ft 6 in
to
5 ft 11 in
5 ft 10 in
to
6 ft 2 in
6 ft 1 in
to
6 ft 5 in

Stack and Reach vs. Category Trend

Very Upright
Somewhat Upright
Average
Somewhat Aggressive
Very Aggressive

The Bike Insights Upright/Aggressive scale is based on analysis of a bike’s proportions relative to similar sized bikes in the same category.

Learn more about the Upright/Aggressive Scale
Category Trend
All-road/Gravel
Source:https://thesis.bike/products/the-ob1-original