Bmc Kaius 01 THREE

A race-ready gravel bike from 2025, made in 6 sizes from 47 to 61. Fits tyres up to 44 mm.

Size

Stack 550 mmReach 401 mm

Geometry

Bmc Kaius 01 THREE geometry by frame size
Size
Fit
Stack (mm)How high the front sits	510	530	550	570	595	620
Reach (mm)How far forward the bars start	390	397	401	405	410	414
Stack ÷ reach Higher = more upright	1.31	1.34	1.37	1.41	1.45	1.50
Top tube (effective) (mm)Horizontal top-tube length	546	559	569	579	592	604
Seat tube angle Saddle position over the pedals	73°	73°	73°	73°	73°	73°
Seat tube length (mm)Frame size reference	428	452	468	493	513	533
Head tube length (mm)Front-end height	85	106	123	144	170	196
Standover (mm)Clearance when you stop	684	722	756	780	798	818
Handling
Head tube angle Steeper = quicker steering	71°	71°	72°	72°	72°	72°
Fork offset (mm)Fork rake	50	50	45	45	45	45
Trail (mm)More = steadier steering	66	66	68	68	68	68
Wheelbase (mm)Longer = more stable	1003	1017	1015	1026	1039	1051
Chainstay (mm)Shorter = snappier	420	420	420	420	420	420
BB drop (mm)More = lower centre of gravity	80	80	80	80	80	80
BB height (mm)Pedal clearance in corners	256	256	256	256	256	256
Front centre (mm)Room for your toes	596	610	608	619	632	644

Underlined values are calculated by BikeLens. A dash means the brand doesn't publish it.

A racy stance with road-bike efficiency on fast, mixed surfaces.

Size 54 is lower and longer than 99% of the 106 gravel frames we track.

The closest gravel frames from other ranges, against size 54 here.

Bikes with a similar fit, compared with size 54 of this bike
Bike	Size	Stack	Reach
Trek Checkpoint ALR 32025Stack +3 mm, reach −2 mm	52	+3 mm	−2 mm
Grind TRACE2026Stack −8 mm, reach −5 mm	S	−8 mm	−5 mm
Cervelo Áspero2025Stack +5 mm, reach −13 mm	54	+5 mm	−13 mm
Canyon Inflite CF SLX 72026Stack −3 mm, reach −13 mm	S	−3 mm	−13 mm
Romet Aspre 1.02026Stack +11 mm, reach +3 mm	M	+11 mm	+3 mm
Megamo SILK 01 SLR2026Stack +7 mm, reach −6 mm	M	+7 mm	−6 mm