2017 Surly Bikes ECR 27+ Base

	XS	S	M
Stack	556mm	580mm	603mm
Reach	385mm	398mm	411mm
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 Center	555mm	575mm	595mm
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 Max	435mm	435mm	435mm
Chainstay Length Horizontal	430.8mm	430.8mm	430.8mm
Chainstay Length Horizontal Max	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
Wheelbase Max	1052.3mm	1074mm	1096mm
Fork Offset/Rake	43mm	42.5mm	42.7mm
Fork Length (Axle-To-Crown)	447mm	447mm	447mm
Trail	95.3mm very high	95.8mm very high	95.6mm very high
Mechanical Trail	89mm	89.4mm	89.3mm
Wheel Flop	31.9mm	32.1mm	32mm
Standover Height	726mm	766mm	802mm
Tire to Pedal Spindle	86.2mm 170 mm cranks	107.8mm 170 mm cranks	129.7mm 170 mm cranks
Pedal Spindle to Ground Clearance	138.2mm 170 mm cranks	138.2mm 170 mm cranks	138.2mm 170 mm cranks

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.

Category Trend

Source:Bike Counterculture Geometry Database

Geometry