	S	M	L	XL
Stack	593.8mm	603mm	612mm	621mm
Reach	425mm	455mm	480mm	510mm
Stack to Reach Ratio	1.4:1	1.33:1	1.27:1	1.22:1
Seat Tube Length, C-T	400mm	410mm	450mm	500mm
Top Tube Length, Effective/Horizontal Center	562.7mm	595.7mm	623.7mm	656.7mm
Top Tube Slope	21.5deg	20.3deg	16.6deg	12.2deg
Head Tube Angle	65deg	65deg	65deg	65deg
Seat Tube Angle	76deg	76deg	76deg	76deg
Head Tube Length	90mm	100mm	110mm	120mm
Bottom Bracket Drop	38mm	38mm	38mm	38mm
Bottom Bracket Height	334mm	334mm	275.4mm	275.4mm
Chainstay Length	435mm	435mm	435mm	435mm
Chainstay Length Horizontal	433.3mm	433.3mm	433.3mm	433.3mm
Front-Center	733.7mm	767.6mm	797.2mm	831.2mm
Front-Center Horizontal	732.7mm	766.7mm	796.3mm	830.4mm
Wheelbase	1166mm	1200mm	1229.6mm	1263.7mm
Fork Offset/Rake	44mm	44mm	44mm	44mm
Fork Length, Unknown	130mm	130mm	130mm	130mm
Trail	124.9mm very high	124.9mm very high	97.6mm very high	97.6mm very high
Mechanical Trail	113.2mm	113.2mm	88.5mm	88.5mm
Wheel Flop	47.8mm	47.8mm	37.4mm	37.4mm
Standover Height	594mm	595mm	719mm	744mm
Tire to Pedal Spindle	191.7mm 170 mm cranks	225.6mm 170 mm cranks	313.8mm 170 mm cranks	347.8mm 170 mm cranks
Pedal Spindle to Ground Clearance	164mm 170 mm cranks	164mm 170 mm cranks	105.4mm 170 mm cranks	105.4mm 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://marinbikes.com/products/2026-tam-1

2026 Marin Bikes Tam 1

Geometry