BMC’s original Kaius arrived with great fanfare; it was an out-and-out aero bike designed for off-road adventures.
I was excited when it was announced. I’d been impressed by the versatile and capable URS, and I had high hopes for the Kaius.
Sadly, it didn’t quite live up to expectations. Yes, it was devastatingly fast in the right conditions (smooth gravel and tarmac), but shift onto anything approaching technical terrain or singletrack and it became a handful.
The flat-out race position, narrow cockpit and skinny, semi-slick tyres all came up as negatives.
The all-new 2026 Kaius 01, however, looks as though it may address the issues I had with its predecessor.
- Read more: Best gravel bikes in 2026 – top-rated carbon, aluminium, titanium and steel gravel bikes reviewed
More adaptable
The first area of improvement is the tyre selection – the new frame and fork can now accommodate up to 52mm gravel tyres while maintaining the ISO-approved 6mm of clearance between tyre and frameset.
However, the geometry is where BMC appears to have played things much smarter. The head angle has steepened slightly to 71º and the fork trail has increased to a large 72mm, up from the road-like 68mm of the original. At the same time, the bottom bracket has been lifted, and the wheelbase and chainstays extended.
The new Kaius also gets a little more stack and a shorter reach, providing a ride position more suited to challenging surfaces.
BMC claims this brings much more technical-terrain capability.
The frameset was designed around 1x drivetrains, with chainring sizes from 32 to 50-tooth, making it possible to use either gravel groupsets or mountain bike drivetrains. It comes with a switchable chain guide, providing security across a wide range of ring sizes.
Finally, BMC has made the frame more versatile, adding a third set of bosses under the down tube and top tube mounts, plus a cargo plate on the underside of the top tube.
More aero, less weight
That BMC has managed to add in greater tyre capacity and more fittings, yet reduce the frame weight is quite an achievement – even if it’s only to the tune of 63g.
Aero improvements come in the form of a new seatpost, borrowed from the new Team Machine SLR 01 and the wide, F1-inspired ‘Halo’ fork also coming from the road-going BMC design catalogue. It shares the same integrated Aerocore cages as found on the Team Machine.
BMC also claims the new Kaius improves its aerodynamic efficiency over the original, although it hasn’t provided any wind-tunnel data.
2026 BMC Kaius 01 specifications and pricing
- Kaius 01 ONE SRAM Red XPLR AXS: £9,999 / $12,999 / €10,999
- Kaius 01 TWO SRAM Force AXS: £7,299 / $8,999 / €7,999
- Kaius 01 THREE SRAM Rival XPLR AXS: £4,999 / $6,199 / €5,499
- Kaius 01 frameset VAR0: £3,999 / $5,099 / €4,499
