2021 Sonder Vir Fortis Base

Design
Flat Bar, Rigid, suspension corrected
Frame
Carbon/Composite
Fork
Carbon/Composite
Features
Disc brake
Somewhat aggressive stack and reachvs category
Somewhat aggressive stack and reachvs category
Average stack and reachvs category

Geometry

Small
Medium
Large
Stack
586mm
595mm
614mm
Reach
406mm
423mm
437mm
Stack to Reach Ratio
1.44:1
1.41:1
1.41:1
Seat Tube Length, Unknown
406mm
457mm
505mm
Top Tube Length, Effective/Horizontal Unknown
580mm
605mm
625mm
Top Tube Slope
20.7deg
15.8deg
12.6deg
Head Tube Angle
68.5deg
68.5deg
68.5deg
Seat Tube Angle
73.5deg
73deg
73deg
Head Tube Length
100mm
110mm
130mm
Bottom Bracket Drop
60mm
60mm
60mm
Bottom Bracket Height
321.1mm
321.1mm
321.1mm
Chainstay Length
445mm
445mm
445mm
Chainstay Length Horizontal
440.9mm
440.9mm
440.9mm
Front-Center
664.8mm
684.7mm
706.6mm
Front-Center Horizontal
662.1mm
682.1mm
704.1mm
Wheelbase
1103mm
1123mm
1145mm
Fork Offset/Rake
45mm
45mm
45mm
Trail
101.8mm
very high
101.8mm
very high
101.8mm
very high
Mechanical Trail
94.7mm
94.7mm
94.7mm
Wheel Flop
34.7mm
34.7mm
34.7mm
Tire to Pedal Spindle
113.7mm
170 mm cranks
133.6mm
170 mm cranks
155.5mm
170 mm cranks
Pedal Spindle to Ground Clearance
151.1mm
170 mm cranks
151.1mm
170 mm cranks
151.1mm
170 mm cranks

Base Build

Small
Medium
Large
Wheel Size
26 in
559 mm BSD
26 in
559 mm BSD
26 in
559 mm BSD
Tire Width
4in
4in
4in
Tire Width Max
4.8in
4.8in
4.8in
Tire Outer Diameter
762.2mm
762.2mm
762.2mm
Bike Length with Tires
1865.2mm
1885.2mm
1907.2mm

Published Sizing Recommendations

Height
5 ft 2 in
to
5 ft 7 in
5 ft 6 in
to
5 ft 10 in
5 ft 9 in
to
6 ft 2 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
Rigid Fatbike
Source:https://alpkit.com/collections/sonder-vir-fortis/products/sonder-vir-fortis-gx-eagle