2026 Transition Bikes Spur Base

	SM	MD	LG	XL
Stack	612mm	621mm	630mm	644mm
Reach	425mm	455mm	480mm	505mm
Stack to Reach Ratio	1.44:1	1.36:1	1.31:1	1.28:1
Seat Tube Length, Unknown	360mm	390mm	430mm	460mm
Top Tube Length, Effective/Horizontal Unknown	570mm	603mm	631mm	660mm
Top Tube Slope	27.3deg	23.9deg	20deg	17.8deg
Head Tube Angle	65.5deg	65.5deg	65.5deg	65.5deg
Seat Tube Angle	76.7deg	76.3deg	75.9deg	75.6deg
Head Tube Length	100mm	110mm	120mm	135mm
Bottom Bracket Drop	47mm	47mm	47mm	47mm
Bottom Bracket Height	325mm	325mm	325mm	325mm
Chainstay Length	436mm	436mm	441mm	441mm
Chainstay Length Horizontal	433.5mm	433.5mm	438.5mm	438.5mm
Front-Center	731.1mm	765mm	793.9mm	824.9mm
Front-Center Horizontal	729.5mm	763.5mm	792.5mm	823.5mm
Wheelbase	1163mm	1197mm	1231mm	1262mm
Fork Offset/Rake	44mm	44mm	44mm	44mm
Trail	121.2mm very high	121.2mm very high	121.2mm very high	121.2mm very high
Mechanical Trail	110.3mm	110.3mm	110.3mm	110.3mm
Wheel Flop	45.7mm	45.7mm	45.7mm	45.7mm
Standover Height	660mm	660mm	660mm	660mm
Tire to Pedal Spindle	194.1mm 165 mm cranks	228mm 165 mm cranks	256.9mm 165 mm cranks	287.9mm 165 mm cranks
Pedal Spindle to Ground Clearance	160mm 165 mm cranks	160mm 165 mm cranks	160mm 165 mm cranks	160mm 165 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://www.transitionbikes.com/Bikes/Spur

Geometry