2018 Chumba Cycles Ursa Major Base

	SM	MD	LG	XL
Stack	607mm	614mm	626mm	638mm
Reach	406mm	424mm	438mm	452mm
Stack to Reach Ratio	1.5:1	1.45:1	1.43:1	1.41:1
Seat Tube Length, C-T	387.3mm	438.2mm	489mm	539.8mm
Top Tube Length, Effective/Horizontal Center	595mm	615mm	635mm	650mm
Top Tube Slope	24.5deg	19.4deg	15.3deg	11.3deg
Head Tube Angle	69deg	69deg	69deg	69.5deg
Seat Tube Angle	72.75deg	72.75deg	72.75deg	72.75deg
Head Tube Length	128mm	135mm	148mm	158mm
Bottom Bracket Drop	50mm	50mm	50mm	50mm
Bottom Bracket Height	356.5mm	356.5mm	356.5mm	356.5mm
Chainstay Length	439mm	439mm	439mm	439mm
Chainstay Length Max	459mm	459mm	459mm	459mm
Chainstay Length Horizontal	436.1mm	436.1mm	436.1mm	436.1mm
Chainstay Length Horizontal Max	456.3mm	456.3mm	456.3mm	456.3mm
Front-Center	671.7mm	692.7mm	711.6mm	723.6mm
Front-Center Horizontal	669.9mm	690.9mm	709.9mm	721.9mm
Wheelbase	1106mm	1127mm	1146mm	1158mm
Wheelbase Max	1126mm	1146mm	1166mm	1178mm
Fork Offset/Rake	46.7mm	47mm	47.4mm	46.9mm
Fork Length (Axle-To-Crown)	483mm	483mm	483mm	483mm
Trail	106mm very high	105.7mm very high	105.3mm very high	102mm very high
Mechanical Trail	99mm	98.7mm	98.3mm	95.5mm
Wheel Flop	35.5mm	35.4mm	35.2mm	33.5mm
Standover Height	660.4mm	692.2mm	717.6mm	749.3mm
Tire to Pedal Spindle	95.2mm 170 mm cranks	116.2mm 170 mm cranks	135.1mm 170 mm cranks	147.1mm 170 mm cranks
Pedal Spindle to Ground Clearance	186.5mm 170 mm cranks	186.5mm 170 mm cranks	186.5mm 170 mm cranks	186.5mm 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.chumbausa.com/ursa-major-titanium-fatbike/

Geometry