Cervélo refines Aspero gravel bike with tweaked frame, greater compliance and more room for mud

Updated Áspero takes influence from Soloist road bike

By Warren Rossiter

Published: Tuesday, 30 April 2024 at 07:01 AM

Cervélo has unveiled the latest iteration of its Áspero gravel race bike, sporting a raft of evolutionary updates including a slimmer down tube and significantly dropped seatstays.

Since its 2019 debut, the Áspero (meaning rough roads) has existed at the racier end of the wide gravel bikes spectrum, with a stripped-back frame and fork, and minimal bikepacking-friendly fixtures.

Continuing that approach, the new Áspero features tube shapes culled from Cervélo’s extensive library, with plenty of the frame’s elements drawing inspiration from its road-going siblings – most obviously the Soloist.

Unlike most new bikes, Cervélo has reduced the Áspero’s frame stiffness in some areas, which it claims improves performance.

Also unlike the plethora of new gravel bikes for 2024 – including the Merida Silex, GT Grade, Santa Cruz Stigmata and Canyon Grail – geometry has been left largely alone.

The focus is instead on improved clearance for mud and chainrings, along with frame-shape tweaks designed to make the Áspero a more agile racer.

Warren Rossiter has spent some time riding the new Cervélo Áspero Rival XPLR AXS and you can read his review here.

Frameset evolution

It’s evolution rather than revolution for the new Áspero. – Cervélo

The new Áspero frame has seen subtle changes rather than a radical redesign. It now has a lower standover height across all sizes, while both chainstays have been dropped further to improve chainring clearance.

Cervélo has looked at the carbon and layup schedule, too, introducing more compliance to the frame and fork.

Most noticeable is the slimmer down tube, along with seatstays that are dropped much further down the seat tube.

Cervélo has decreased the head-tube stiffness to 95Nm/deg from the 110Nm/deg of the original and 112Nm/deg of the premium Áspero 5. However, bottom-bracket stiffness is up on the original 228Nm/deg versus 220, but less than the Áspero 5’s ultra-stiff 240Nm/deg.

Cervélo Áspero gravel bike — Improving compliance without compromising the bike’s handling was the priority. – Cervélo

The goal for the new bike was to maintain the Áspero’s performance-oriented handling, but improve compliance through the saddle and bar, while retaining drivetrain efficiency.

Also outgoing is Cérvelo’s long-standing press-fit BBRight bottom bracket, in favour of a threaded BBRight T47-A. It’s the same unit used on the Soloist – and it’s not the only tech borrowed from the brand’s all-rounder aero road bike.

Up-front, the new Áspero shares the ST36 system, where the hoses are semi-integrated into the frame using a D-shaped fork steerer.

For bikes with mechanical drivetrains, Cervélo offers a new cable-management system called the ‘clippy clip’. Here, a split bearing cap (available in 14mm and 30mm depths) enables the cables to be channelled, along with the hoses, through the head tube.

The cables and hoses don’t run fully internally through the stem, making servicing and transporting the bike easier.

A lot of Cervélo’s rivals have moved closer to MTB-inspired geometry, with long front-centres, longer forks and slacker head angles.

However, Cervélo has stuck to its steeper, road-oriented head angle (72 degrees on sizes 54, 56, 58 and 61cm; 71/71.5 on 48 and 51cm respectively). It’s similarly steep at the rear – 73 degrees (56, 58, 61cm), 73.5 (54cm), 74 (51cm) and 74.5 (48cm).

The new frame offers 7.4mm of mud clearance with a 700x42c tyre, thanks to chainstays that have increased to 425mm from 420mm. The wheelbase is only a millimetre longer in a size 56cm.

The fork offers the same clearance and Cervélo has kept the switchable dropout it calls the Trail Mixer.

Cervélo’s fork dropout insert alters the position of the fork offset fore and aft by 5mm horizontally. It claims this means the bike will feel the same running a relatively slender tyre on a 700c wheel, compared to a maxed-out 42mm gravel tyre.

The fork’s chin has a much cleaner integration into the head tube, which is reminiscent of the Soloist. Like the original Áspero, the new bike retains its three bottle boss sets, down tube protector and bento box mounts on the top tube.

Mud clearance on the drivetrain is also improved. With a 46-tooth chainring, there’s 2.7mm clearance, 1.8mm with a 48-tooth ring and 3.2mm for a 52-tooth ring.

The dropped seatstays influence a revised seat-tube shape with a much more prominent wheel cut-out. The seatpost has a standard 27.2mm diameter and is compatible with gravel dropper posts, while the rear dropout is now SRAM Universal Derailleur Hanger compliant.

	48	51	54	56	58	61
Seat tube angle (degrees)	74.5	74	73.5	73	73	73
Head tube angle (degrees)	71	71.5	72	72	72	72
Chainstay (mm)	420	420	420	420	420	420
Top tube (mm)	512	532	553	575	591	608
Head tube (mm)	83	107	133	159	188	214
Fork offset (mm)	53	49	46	46	46	46
Trail (mm)	58.6	58.6	58.6	58.6	58.6	58.6
Bottom bracket drop (mm)	78.5	78.5	76	76	73.5	73.5
Wheelbase (mm)	990	1000	1010	1027	1046	1063
Standover (mm)	690	732	764	788	814	838
Stack (mm)	505	530	555	580	605	630
Reach (mm)	370	379	388	397	406	415

Edit Table

2024 Cervélo Áspero range details

The Áspero is part of Cervélo’s Experiential range, alongside the Caledonia, Soloist and Rouvida e-road bike.

Don’t expect any superbike builds, as found on the S5 and R5, because the range tops out with a SRAM Rival AXS XPLR model that gets Reserve 40/44 gravel wheels, at £5,200.

The UK range opens with a Shimano GRX610 2x 12-speed model, with Alexrims Boondocks wheels, at £3,100. International buyers will find both a GRX400 model for $2,400 and a mechanical Apex XPLR 1 model at $3,500.

The premium Áspero 5, with its lighter, stiffer frameset and D-shaped seatpost, remains in the range.