2021 Thesis Bike OB1 Base (650B)

	XS	S	M	L	XL
Stack	521mm	551mm	571mm	595mm	614mm
Reach	356mm	363mm	378mm	388mm	403mm
Stack to Reach Ratio	1.46:1	1.52:1	1.51:1	1.53:1	1.52:1
Seat Tube Length, C-T	440mm	470mm	500mm	530mm	560mm
Top Tube Length, Effective/Horizontal HT Top	515mm	531mm	547mm	570mm	591mm
Top Tube Slope	11.7deg	11.5deg	10deg	9.2deg	7.9deg
Head Tube Angle	70deg	71deg	72deg	72deg	72deg
Seat Tube Angle	73deg	73deg	73deg	73deg	73deg
Head Tube Length	110mm	138mm	155mm	180mm	200mm
Bottom Bracket Drop	73mm	73mm	73mm	73mm	73mm
Bottom Bracket Height	266mm	266mm	266mm	266mm	266mm
Chainstay Length	420mm	420mm	420mm	420mm	420mm
Chainstay Length Horizontal	413.6mm	413.6mm	413.6mm	413.6mm	413.6mm
Front-Center	578mm	586mm	598mm	616mm	637mm
Front-Center Horizontal	573.4mm	581.4mm	593.4mm	611.4mm	632.4mm
Wheelbase	987mm	995mm	1007mm	1025mm	1046mm
Fork Offset/Rake	51mm	51mm	51mm	51mm	51mm
Fork Length (On-Axis)	385mm	385mm	385mm	385mm	385mm
Trail	69.1mm high	62.8mm mid/neutral	56.5mm mid/neutral	56.5mm mid/neutral	56.5mm mid/neutral
Mechanical Trail	64.9mm	59.4mm	53.8mm	53.8mm	53.8mm
Wheel Flop	22.2mm	19.3mm	16.6mm	16.6mm	16.6mm
Standover Height	720mm	750mm	775mm	805mm	835mm
Tire to Pedal Spindle	84mm 155 mm cranks	87mm 160 mm cranks	94mm 165 mm cranks	107mm 170 mm cranks	123mm 175 mm cranks
Pedal Spindle to Ground Clearance	111mm 155 mm cranks	106mm 160 mm cranks	101mm 165 mm cranks	96mm 170 mm cranks	91mm 175 mm cranks

Published Sizing Recommendations

Height

5 ft 1 in

5 ft 5 in

5 ft 4 in

5 ft 8 in

5 ft 6 in

5 ft 11 in

5 ft 10 in

6 ft 2 in

6 ft 1 in

6 ft 5 in

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.

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Source:https://thesis.bike/products/the-ob1-original