2026 Sour Bicycles Purple Pie Pinion

	XS	SM	MD	LG	XL
Stack	540.3mm	554.4mm	593.9mm	602.1mm	628.5mm
Reach	374.2mm	378.2mm	377.6mm	382.7mm	383.8mm
Stack to Reach Ratio	1.44:1	1.47:1	1.57:1	1.57:1	1.64:1
Seat Tube Length, C-T	450mm	480mm	510mm	540mm	570mm
Top Tube Length, Effective/Horizontal HT Top	519mm	532mm	545mm	561mm	576mm
Top Tube Slope	12.2deg	10.3deg	11.3deg	8.9deg	8.6deg
Head Tube Angle	70.5deg	70.5deg	70.5deg	71.5deg	71.5deg
Seat Tube Angle	75deg	74.5deg	74deg	73.5deg	73deg
Head Tube Length	120mm	135mm	145mm	160mm	190mm
Bottom Bracket Drop	72mm	72mm	72mm	72mm	70mm
Bottom Bracket Height	289mm	289mm	289mm	289mm	291mm
Chainstay Length	440mm	440mm	440mm	440mm	440mm
Chainstay Length Horizontal	434.1mm	434.1mm	434.1mm	434.1mm	434.4mm
Front-Center	602.1mm	604.2mm	610.2mm	612.2mm	621.6mm
Front-Center Horizontal	597.7mm	599.9mm	605.9mm	607.9mm	617.6mm
Wheelbase	1031.8mm	1034mm	1040mm	1042mm	1052mm
Fork Offset/Rake	45mm	45mm	45mm	45mm	45mm
Fork Length (On-Axis)	405mm	405mm	405mm	405mm	405mm
Trail	80.1mm very high	80.1mm very high	80.1mm very high	73.3mm high	73.3mm high
Mechanical Trail	75.5mm	75.5mm	75.5mm	69.6mm	69.6mm
Wheel Flop	25.2mm	25.2mm	25.2mm	22.1mm	22.1mm
Tire to Pedal Spindle	71.1mm 170 mm cranks	73.2mm 170 mm cranks	79.2mm 170 mm cranks	81.2mm 170 mm cranks	90.6mm 170 mm cranks
Pedal Spindle to Ground Clearance	119mm 170 mm cranks	119mm 170 mm cranks	119mm 170 mm cranks	119mm 170 mm cranks	121mm 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:https://sour.bike/bikes/gravel/purple-pie/

Geometry