Compare: 2025 LightCarbon LCG071S-PRO Base 490 vs 2026 TanTan Cycling (Seraph) GR257 Base 510

Insights

Average stack and reach vs trend of all-road/gravel bikes

Design deviates from other sizes of LightCarbon LCG071S-PRO

Somewhat upright stack and reach vs trend of progressive gravel bikes

Design deviates from other sizes of TanTan Cycling (Seraph) GR257

Stack	542.6mm	540mm -2.6mm
Reach	374.1mm	369mm -5.1mm
Stack to Reach Ratio	1.45:1	1.46:1
Seat Tube Length, C-TTT	—	488mm
Seat Tube Length, Unknown	490mm	—
Top Tube Length, Effective/Horizontal Center	—	521mm
Top Tube Length, Effective/Horizontal Unknown	535mm	—
Top Tube Slope	8.1deg	5.7deg -2.4deg
Head Tube Angle	71deg	71deg +0deg
Seat Tube Angle	73.5deg	74.3deg +0.8deg
Head Tube Length	120mm	108mm -12mm
Bottom Bracket Drop	70mm	72mm +2mm
Bottom Bracket Height	281mm	289mm +8mm
Chainstay Length	430mm	435mm +5mm
Chainstay Length Horizontal	424.3mm	429mm +4.7mm
Front-Center	593.8mm	593.4mm -0.4mm
Front-Center Horizontal	584.6mm	589mm +4.4mm
Wheelbase	1008.9mm	1018mm +9.1mm
Fork Offset/Rake	50mm	55mm +5mm
Fork Length (On-Axis)	397mm	—
Fork Length, Unknown	—	405mm
Trail	68mm high	66.1mm -1.9mm high
Mechanical Trail	64.3mm	62.5mm -1.8mm
Wheel Flop	20.9mm	20.4mm -0.5mm
Tire to Pedal Spindle	72.8mm 170 mm cranks	62.4mm -10.4mm 170 mm cranks
Pedal Spindle to Ground Clearance	111mm 170 mm cranks	119mm +8mm 170 mm cranks

Wheel Size	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD
Tire Width	40mm	50mm +10mm
Tire Width Max	53mm	57mm +4mm
Tire Outer Diameter	702mm	722mm +20mm
Bike Length with Tires	1710.9mm	1740mm +29.1mm
Suspension Type	Rigid, non-suspension corrected	Rigid, non-suspension corrected
Bar Type	Drop Bar	Drop Bar
Frame Material	Carbon/Composite	Carbon/Composite
Fork Material	Carbon/Composite	Carbon/Composite
Brake Type	Disc	Disc