Compare: 2023 Seaboard GR02 Base 59 vs 2025 Factor Bikes OSTRO GRAVEL Carbon 61

Insights

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

Design deviates from other sizes of Seaboard GR02

Somewhat upright stack and reach vs trend of progressive gravel bikes

Design deviates from other sizes of Factor Bikes OSTRO GRAVEL

Stack	611.8mm	625mm +13.2mm
Reach	404.5mm	422mm +17.5mm
Stack to Reach Ratio	1.51:1	1.48:1
Seat Tube Length, C-T	—	545mm
Seat Tube Length, Unknown	590mm	—
Top Tube Length, Effective/Horizontal Unknown	580mm	—
Top Tube Slope	4.5deg	10.1deg +5.6deg
Head Tube Angle	72deg	72.3deg +0.3deg
Seat Tube Angle	74deg	73.5deg -0.5deg
Head Tube Length	19mm	—
Bottom Bracket Drop	70mm	74mm +4mm
Bottom Bracket Height	278mm	277mm -1mm
Chainstay Length	425mm	425mm +0mm
Chainstay Length Horizontal	419.2mm	418.5mm -0.7mm
Front-Center	637.1mm	654.7mm +17.6mm
Front-Center Horizontal	633.2mm	650.5mm +17.3mm
Wheelbase	1052.4mm	1069mm +16.6mm
Fork Offset/Rake	50.1mm	50mm -0.1mm
Trail	60.4mm mid/neutral	59.5mm -0.9mm mid/neutral
Mechanical Trail	57.5mm	56.7mm -0.8mm
Wheel Flop	17.8mm	17.2mm -0.6mm
Standover Height	—	847mm
Tire to Pedal Spindle	119.1mm 170 mm cranks	133.7mm +14.6mm 170 mm cranks
Pedal Spindle to Ground Clearance	108mm 170 mm cranks	107mm -1mm 170 mm cranks

Wheel Size	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD
Tire Width	37mm	40mm +3mm
Tire Outer Diameter	696mm	702mm +6mm
Bike Length with Tires	1748.4mm	1771mm +22.6mm
Suspension Type	Rigid, non-suspension corrected	Rigid, non-suspension corrected
Bar Type	Drop Bar	Drop Bar
Frame Material	Aluminum	Carbon/Composite
Fork Material	Carbon/Composite	Carbon/Composite
Brake Type	Disc	Disc

Actions	Collection I've Ridden	Collection I've Ridden
Source	https://tsunamibicycle.com/product/seaboard-gr02-2022-gravel-bike-off-road-bike-touring-bike/	https://factorbikes.com/bikes/ostro-gravel
Brand	Seaboard	Factor Bikes
Bike	2023 GR02 Base	2025 OSTRO GRAVEL Carbon
Size	59	61
Category	All-road/Gravel	Progressive Gravel