2025 Tunk Hike-Use Base

	53	55	57	59	61	63	65
Stack	535mm	555mm	575mm	595mm	615mm	636mm	660mm
Reach	356mm	365mm	374mm	382mm	396mm	400mm	407mm
Stack to Reach Ratio	1.5:1	1.52:1	1.54:1	1.56:1	1.55:1	1.59:1	1.62:1
Seat Tube Length, C-T	552mm	574mm	595mm	616mm	637mm	654mm	684mm
Seat Tube Length, C-C	524mm	544mm	566mm	586mm	603mm	629mm	660mm
Top Tube Length, Effective/Horizontal Center	525mm	540mm	555mm	569mm	585mm	600mm	615mm
Top Tube Length, Actual C-C	525mm	540mm	555mm	569mm	585mm	600mm	615mm
Top Tube Slope	0deg	0deg	0deg	0deg	0deg	0deg	0deg
Head Tube Angle	72deg	72deg	73deg	73deg	73deg	73deg	73deg
Seat Tube Angle	72.5deg	72.5deg	72.5deg	72.5deg	72.5deg	72.5deg	72.5deg
Head Tube Length	148mm	149mm	166mm	187mm	174mm	194mm	220mm
Bottom Bracket Drop	56mm	64mm	64mm	64mm	78mm	78mm	78mm
Bottom Bracket Height	265.5mm	270mm	270mm	270mm	275mm	275mm	275mm
Chainstay Length	428mm	440mm	440mm	440mm	460mm	460mm	460mm
Chainstay Length Horizontal	424.3mm	435.3mm	435.3mm	435.3mm	453.3mm	453.3mm	453.3mm
Front-Center	583mm	596mm	602mm	615mm	633mm	643mm	658mm
Front-Center Horizontal	580.3mm	592.6mm	598.6mm	611.7mm	628.2mm	638.3mm	653.4mm
Wheelbase	1004.6mm	1027.9mm	1033.9mm	1047mm	1081.5mm	1091.6mm	1106.7mm
Fork Offset/Rake	65mm	65mm	65mm	65mm	65mm	65mm	65mm
Fork Length (Axle-To-Crown)	363mm	375mm	375mm	375mm	395mm	395mm	395mm
Trail	36.1mm low	40.2mm low	34.1mm low	34.1mm low	40mm low	40mm low	40mm low
Mechanical Trail	34.4mm	38.2mm	32.7mm	32.7mm	38.2mm	38.2mm	38.2mm
Wheel Flop	10.6mm	11.8mm	9.6mm	9.6mm	11.2mm	11.2mm	11.2mm
Standover Height	770mm	800mm	820mm	840mm	860mm	890mm	915mm
Tire to Pedal Spindle	96.5mm 165 mm cranks	97mm 165 mm cranks	98mm 170 mm cranks	111mm 170 mm cranks	110mm 170 mm cranks	115mm 175 mm cranks	125mm 180 mm cranks
Pedal Spindle to Ground Clearance	100.5mm 165 mm cranks	105mm 165 mm cranks	100mm 170 mm cranks	100mm 170 mm cranks	105mm 170 mm cranks	100mm 175 mm cranks	95mm 180 mm cranks

	53	55	57	59	61	63	65
Wheel Size	26 in 559 mm BSD	650B/27.5 in 584 mm BSD	650B/27.5 in 584 mm BSD	650B/27.5 in 584 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD
Tire Width	42mm	42mm	42mm	42mm	42mm	42mm	42mm
Tire Width Max	48mm	48mm	48mm	48mm	48mm	48mm	48mm
Tire Outer Diameter	643mm	668mm	668mm	668mm	706mm	706mm	706mm
Bike Length with Tires	1647.6mm	1695.9mm	1701.9mm	1715mm	1787.5mm	1797.6mm	1812.7mm
Crank Length	165mm	165mm	170mm	170mm	170mm	175mm	180mm

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.

Learn more about the Upright/Aggressive Scale

Category Trend

Low-trail

Source:designer input

Suggest Bike Edit

2025 Tunk Hike-Use Base

Geometry

Base Build

Stack and Reach vs. Category Trend