2021 Surly Bikes ECR 27+ Base

Category
Rigid MTB
Design
Flat Bar, Rigid, non-suspension corrected
Frame
Steel
Fork
Steel
Features
Disc brake
Somewhat aggressive stack and reachvs category
Average stack and reachvs category
Average stack and reachvs category

Geometry

XS
S
M
Stack
556mm
579.5mm
603mm
Reach
385mm
398mm
410.5mm
Stack to Reach Ratio
1.44:1
1.46:1
1.47:1
Seat Tube Length, C-T
346.4mm
406.4mm
457.2mm
Top Tube Length, Effective/Horizontal HT Top
555mm
575mm
595mm
Top Tube Length, Actual C-C
536.3mm
547mm
563.1mm
Top Tube Slope
24.8deg
20.3deg
16.9deg
Head Tube Angle
69deg
69deg
69deg
Seat Tube Angle
73deg
73deg
73deg
Head Tube Length
90mm
115mm
140mm
Bottom Bracket Drop
60mm
60mm
60mm
Bottom Bracket Height
308.2mm
308.2mm
308.2mm
Chainstay Length
435mm
435mm
435mm
Chainstay Length Horizontal
430.8mm
430.8mm
430.8mm
Front-Center
624.4mm
646mm
667.9mm
Front-Center Horizontal
621.5mm
643.2mm
665.2mm
Wheelbase
1052.3mm
1074mm
1096mm
Fork Offset/Rake
43.2mm
43.2mm
43.2mm
Fork Length (Axle-To-Crown)
447mm
447mm
447mm
Trail
95.1mm
very high
95.1mm
very high
95.1mm
very high
Mechanical Trail
88.8mm
88.8mm
88.8mm
Wheel Flop
31.8mm
31.8mm
31.8mm
Standover Height
726mm
766mm
802mm
Tire to Pedal Spindle
86.2mm
170 mm cranks
107.8mm
170 mm cranks
124.7mm
175 mm cranks
Pedal Spindle to Ground Clearance
138.2mm
170 mm cranks
138.2mm
170 mm cranks
133.2mm
175 mm cranks

Base Build

XS
S
M
Wheel Size
650B/27.5 in
584 mm BSD
650B/27.5 in
584 mm BSD
650B/27.5 in
584 mm BSD
Tire Width
3in
3in
3in
Tire Outer Diameter
736.4mm
736.4mm
736.4mm
Bike Length with Tires
1788.7mm
1810.4mm
1832.4mm
Crank Length
170mm
170mm
175mm
Handlebar Width
685mm
685mm
735mm
Stem Length
60mm
60mm
70mm
Stem Angle
6deg
6deg
6deg

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 MTB
Source:https://surlybikes.com/bikes/ecr