	XS	S	M	L	XXL	XL
Stack	526mm	535mm	546mm	561mm	602mm	674mm
Reach	360mm	370mm	380mm	390mm	412mm	400mm
Stack to Reach Ratio	1.46:1	1.45:1	1.44:1	1.44:1	1.46:1	1.69:1
Seat Tube Length, C-T	435mm	447mm	471mm	491mm	577mm	532mm
Top Tube Length, Effective/Horizontal Center	506mm	525mm	547mm	566mm	605mm	585mm
Top Tube Slope	12.6deg	12deg	10.4deg	9.6deg	4.9deg	16.6deg
Head Tube Angle	70deg	70deg	71deg	71deg	71deg	71deg
Seat Tube Angle	76deg	75deg	74deg	74deg	73deg	73deg
Head Tube Length	80mm	100mm	120mm	140mm	190mm	165mm
Bottom Bracket Drop	72mm	72mm	70mm	70mm	68mm	68mm
Bottom Bracket Height	284mm	284mm	286mm	286mm	288mm	288mm
Chainstay Length	435mm	435mm	435mm	435mm	435mm	435mm
Chainstay Length Horizontal	429mm	429mm	429.3mm	429.3mm	429.7mm	429.7mm
Front-Center	574mm	577mm	581mm	593mm	616mm	606mm
Front-Center Horizontal	591mm	603mm	601.7mm	616.7mm	648.4mm	631.4mm
Wheelbase	1020mm	1032mm	1031mm	1046mm	1078mm	1061mm
Fork Offset/Rake	55mm	55mm	50mm	50mm	50mm	50mm
Fork Length (On-Axis)	412mm	412mm	412mm	412mm	412mm	412mm
Trail	71mm high	71mm high	69.7mm high	69.7mm high	69.7mm high	69.7mm high
Mechanical Trail	66.8mm	66.8mm	65.9mm	65.9mm	65.9mm	65.9mm
Wheel Flop	22.8mm	22.8mm	21.5mm	21.5mm	21.5mm	21.5mm
Standover Height	715mm	730mm	755mm	773mm	838mm	807mm
Tire to Pedal Spindle	53mm 165 mm cranks	56mm 165 mm cranks	55mm 170 mm cranks	67mm 170 mm cranks	87.5mm 172.5 mm cranks	77.5mm 172.5 mm cranks
Pedal Spindle to Ground Clearance	119mm 165 mm cranks	119mm 165 mm cranks	116mm 170 mm cranks	116mm 170 mm cranks	115.5mm 172.5 mm cranks	115.5mm 172.5 mm cranks

	XS	S	M	L	XXL	XL
Wheel Size	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD
Tire Width	45mm	45mm	45mm	45mm	45mm	45mm
Tire Width Max	55mm	55mm	55mm	55mm	55mm	55mm
Tire Outer Diameter	712mm	712mm	712mm	712mm	712mm	712mm
Bike Length with Tires	1732mm	1744mm	1743mm	1758mm	1790mm	1773mm
Crank Length	165mm	165mm	170mm	170mm	172.5mm	172.5mm
Handlebar Width	370mm	370mm	390mm	390mm	410mm	410mm
Stem Length	70mm	70mm	80mm	90mm	100mm	100mm

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://xds.co/en-us/products/gt8

2026 XDS X-LAB GT8 Base

Geometry