2017 Surly Bikes ECR 29+ Base

	M	L	XL
Stack	610mm	633mm	657mm
Reach	408mm	421mm	433mm
Stack to Reach Ratio	1.5:1	1.5:1	1.52:1
Seat Tube Length, C-T	457.2mm	507.9mm	558.7mm
Top Tube Length, Effective/Horizontal Center	600mm	620mm	640mm
Top Tube Slope	17.7deg	14.5deg	11.7deg
Head Tube Angle	70deg	70deg	70deg
Seat Tube Angle	72.5deg	72.5deg	72.5deg
Head Tube Length	100mm	125mm	150mm
Bottom Bracket Drop	80mm	80mm	80mm
Bottom Bracket Height	307.2mm	307.2mm	307.2mm
Chainstay Length	451mm	451mm	451mm
Chainstay Length Max	451mm	451mm	451mm
Chainstay Length Horizontal	443.9mm	443.9mm	443.9mm
Chainstay Length Horizontal Max	443.9mm	443.9mm	443.9mm
Front-Center	651.1mm	671.9mm	693.3mm
Front-Center Horizontal	646.2mm	667.2mm	688.7mm
Wheelbase	1090mm	1111mm	1132.5mm
Wheelbase Max	1090mm	1111mm	1132.5mm
Fork Offset/Rake	43mm	43mm	43mm
Fork Length (Axle-To-Crown)	468mm	468mm	468mm
Trail	95.2mm very high	95.2mm very high	95.2mm very high
Mechanical Trail	89.4mm	89.4mm	89.4mm
Wheel Flop	30.6mm	30.6mm	30.6mm
Standover Height	805mm	840mm	875mm
Tire to Pedal Spindle	93.9mm 170 mm cranks	114.7mm 170 mm cranks	136.1mm 170 mm cranks
Pedal Spindle to Ground Clearance	137.2mm 170 mm cranks	137.2mm 170 mm cranks	137.2mm 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