2025 FiftyOne Sika Base

	XS	S	M	L	XL
Stack	515mm	537mm	555mm	578mm	603mm
Reach	360mm	370mm	380mm	390mm	400mm
Stack to Reach Ratio	1.43:1	1.45:1	1.46:1	1.48:1	1.51:1
Seat Tube Length, C-T	470mm	490mm	510mm	530mm	550mm
Top Tube Length, Effective/Horizontal Center	510mm	526mm	546mm	562mm	584mm
Top Tube Slope	7.4deg	7.4deg	7.2deg	7.4deg	7.8deg
Head Tube Angle	70.8deg	71deg	71.2deg	72.6deg	72.8deg
Seat Tube Angle	74deg	74deg	73.5deg	73.5deg	73deg
Head Tube Length	93.2mm	115.7mm	134mm	150mm	175.5mm
Bottom Bracket Drop	78mm	78mm	78mm	78mm	78mm
Bottom Bracket Height	273mm	273mm	273mm	273mm	273mm
Chainstay Length	418mm	418mm	420mm	410mm	422mm
Chainstay Length Horizontal	410.7mm	410.7mm	412.7mm	402.5mm	414.7mm
Front-Center	577mm	592mm	607mm	602mm	618mm
Front-Center Horizontal	571.3mm	587.3mm	601.3mm	607.5mm	612.3mm
Wheelbase	982mm	998mm	1014mm	1010mm	1027mm
Fork Offset/Rake	56mm	56mm	56mm	48mm	48mm
Fork Length (Axle-To-Crown)	388mm	388mm	388mm	388mm	388mm
Trail	62.9mm mid/neutral	61.6mm mid/neutral	60.3mm mid/neutral	59.7mm mid/neutral	58.4mm mid/neutral
Mechanical Trail	59.4mm	58.3mm	57.1mm	57mm	55.8mm
Wheel Flop	19.6mm	19mm	18.4mm	17mm	16.5mm
Standover Height	743mm	763.2mm	782.2mm	803mm	824.8mm
Tire to Pedal Spindle	56mm 170 mm cranks	71mm 170 mm cranks	86mm 170 mm cranks	81mm 170 mm cranks	97mm 170 mm cranks
Pedal Spindle to Ground Clearance	103mm 170 mm cranks	103mm 170 mm cranks	103mm 170 mm cranks	103mm 170 mm cranks	103mm 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://fiftyonebikes.com/wp-content/uploads/2024/04/FiftyOne-Sika-Geo-Bar-Stem-Table-.pdf

Geometry