Name: 2026 Jan Janssen Spirit Base
Brand: Jan Janssen

	S	M	L	XL
Stack	552mm	586mm	611mm	616mm
Reach	362mm	370mm	384mm	407mm
Stack to Reach Ratio	1.52:1	1.58:1	1.59:1	1.51:1
Seat Tube Length, Effective Center	500mm	530mm	560mm	590mm
Top Tube Length, Effective/Horizontal Center	536mm	552mm	568mm	595mm
Top Tube Length, Actual C-C	520.2mm	534.5mm	551mm	577.8mm
Top Tube Slope	8.1deg	8.5deg	7.8deg	7deg
Head Tube Angle	69.5deg	71deg	72.5deg	73deg
Seat Tube Angle	74deg	73.5deg	73.5deg	73deg
Head Tube Length	120mm	150mm	170mm	180mm
Bottom Bracket Drop	70mm	70mm	70mm	70mm
Bottom Bracket Height	281mm	281mm	281mm	281mm
Chainstay Length	430mm	430mm	430mm	430mm
Chainstay Length Horizontal	424.3mm	424.3mm	424.3mm	424.3mm
Front-Center	595.9mm	599.8mm	607.8mm	627.7mm
Front-Center Horizontal	591.7mm	595.7mm	603.7mm	623.7mm
Wheelbase	1016mm	1020mm	1028mm	1048mm
Fork Offset/Rake	45mm	45mm	45mm	45mm
Fork Length (Axle-To-Crown)	400mm	400mm	400mm	400mm
Trail	83.2mm very high	73.3mm high	63.5mm mid/neutral	60.3mm mid/neutral
Mechanical Trail	77.9mm	69.3mm	60.6mm	57.6mm
Wheel Flop	27.3mm	22.6mm	18.2mm	16.9mm
Tire to Pedal Spindle	74.9mm 170 mm cranks	78.8mm 170 mm cranks	86.8mm 170 mm cranks	106.7mm 170 mm cranks
Pedal Spindle to Ground Clearance	111mm 170 mm cranks	111mm 170 mm cranks	111mm 170 mm cranks	111mm 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://www.janjanssen.nl/fietsen/gravel/Spirit

2026 Jan Janssen Spirit Base

Geometry