It was only a matter of time before Cervelo made its racey gravel bike look more like its ultra-fast aero road bike, the S5. And for the most part, that’s exactly what the Cervelo Áspero-5 has become. The new Áspero-5 combines the aero-look front end of the Caledonia-5 all-road bike, the curved seat tube of the S5, and adds some of its own features.
Here’s the thing: I think this is a good gravel bike, even a great one, considering the parameters Cervelo defines the bike was designed for. It’s just not the gravel bike for most people.
So while this isn’t a gravel bike for everyone, it has certainly got me thinking that this is one of the very best all-road bikes I’ve ever ridden, at least as equipped. Allow me to explain.
Quick hits: Seven things to know about the Cervelo Áspero-5
- The Cervelo Áspero-5 is the second generation of the Canadian-American brand’s go-fast gravel bike
- Max tire clearance: 700c x 45 mm (claimed)
- Frameset is claimed to be 66 grams lighter than the outgoing Áspero-5
- Weight (claimed): 990 g (frame); 393 g (fork); 183 g (seat post)
- Claimed 34 Watts more aerodynamic than the fastest gravel bikes Cervelo has tested
- Cost: starting at $5,500 (frameset); $8,700 (Force AXS/X0 Transmission build)
- For more: cervelo.com
Build details
There’s one big number that seems to define the new Áspero-5: 34. That number represents the number of watts that Cervelo claims the bike saves over the next fastest gravel bike in testing. How they arrived at that number is a story of aero optimization that’s both obvious and stuff that’s a bit less so.
The most obvious change has to be at the seat tube, which wraps around the curvature of the rear tire in much the same way that the S5 aero bike does. Doing so smooths turbulent air in an otherwise turbulent area, even if it limits tire clearance to a claimed 45 mm out back. Cervelo says the top tube angles are much the same as the S5, both as a way to create a resemblance between the bikes and take advantage of already-vetted aero details.
The front end of the bike doesn’t pull from the S5, but it shares a lot of similarities with the Soloist and Caledonia-5 road bikes. All Aspero-5 bikes get fully internal cable routing, using Cervelo’s fully internal carbon stem. The bike comes with several headset upper bearing covers, however, riders should decide to use a non-Cervelo stem.
And yes, I’m talking about a separate handlebar and stem, and not a one-piece combination that is popular on most high-end, go-fast gravel bikes. Rather, the Aspero-5 uses a new handlebar designed specifically for the bike. Cervelo says its shape pulls from the AB05 handlebar found on early versions of the S5 that folks loved.
There’s an outcropping ahead of the stem faceplate that smooths airflow around an otherwise non-aero standard stem. Paired with the deep aero profile, Cervelo says its new aero gravel bar saves nearly 6 watts (5.7 watts more specifically) on its own. And while Cervelo did look at a one-piece handlebar for the bike, it found this bar and stem combo met all of the performance goals they had for the bike, but still meant riders could easily swap stuff around without much issue.
Then there are the choices for aero efficiency that are less obvious. My favorite choice has to be the built-in chain keeper, which mounts to the top of the bottom bracket shell rather than along the seat tube (where you can still fit a front derailleur if you’re so inclined. The chain keeper works with anything between a 42t and 52t chainring, but Cervelo found this method was more aerodynamic than using just a traditional chain catcher.
Downtube storage also helps, at least when compared to using a saddle bag. While Cervelo didn’t offer up any aero gains from removing a saddle bag (unlike what Factor did for its Monza road bike), the storage hatch has been updated since the troubles we had on the Caledonia-5 to make it compatible with more bottle cages. And to make it even easier, Cervelo now includes a pair of Arundel Mandible carbon cages with every Aspero-5 to make the choice easy. Finally!
Why did Cervelo stick road tires on a gravel bike?
The first thing I said when I pulled the Aspero-5 out to build it was why Cervelo installed road tires on a gravel bike from the factory. It had to be a mistake, right? Vittoria Corsa Pro Control is a road tire, after all. Then I took a deeper look and saw the sidewall: 42 mm. That’s gravel tire width, right?
I then went to Vittoria to see what was up with this tire, as it’s not currently on the Vittoria website. As it turns out, this was a concerted effort from Cervelo to make a tire that best suited the goals of the Cervelo Aspero-5. Here’s what Maria Benson, Cervelo Director of Product Management, had to say:
“We understand that this choice might be disruptive, but we believe this is a great tire for the goals we set out for the Áspero – to succeed at places like SBT GRVL, UCI Worlds, BWR California, and faster races like that.
But tires are very personal and course-dependent. What is the fastest option for the customer? We felt this was the fastest tire for the events we wanted to optimize the bike for.”
There’s nothing wrong with optimizing a tire for the event, which is what this Aspero-5 is all about. But the tire choice here indicates that this isn’t a bike optimized for muddy editions of Unbound, but for smooth dirt.
Oh, and the aero gains? They’re massive with a slick tire like this. Cervelo says it tested all the tires it could get in, and found the fastest tires were almost always slicks. Semi-slicks weren’t always fast aerodynamically, but slick tires? Absolutely.
Vittoria says this 42 mm Corsa Pro Control tire is made specifically for bike brands who requested them, and that these tires will be available in the aftermarket later this year. For the time being, these tires feature the same casing design and rubber as the road-going Corsa Pro tires. The only difference is width.
There’s no getting around the fact that that ‘34 watts faster than the current most aerodynamically efficient gravel bike’ is at least partially due to the tire choice here. I’d chalk it up to Cervelo optimizing for a very specific gravel audience, for better or worse.
Geometry
| Geometry Chart (Balanced/Mixed geometry) | 48 cm | 51 cm | 54 cm | 56 cm | 58 cm | 61 cm |
|---|---|---|---|---|---|---|
| STACK | 500 / 500 | 525 / 525 | 550 / 550 | 575 / 575 | 600 / 600 | 625 / 625 |
| REACH | 369 / 369 | 377 / 377 | 386 / 386 | 395 / 395 | 404 / 404 | 413 / 413 |
| SEAT TUBE ANGLE (degrees) | 74.1 / 74.1 | 73.6 / 73.6 | 73.1 / 73.1 | 72.6 / 72.6 | 72.6 / 72.6 | 72.6 / 72.6 |
| EFFECTIVE TT LENGTH | 516 / 516 | 531 / 531 | 552 / 552 | 574 / 574 | 591 / 591 | 607 / 607 |
| HEAD TUBE ANGLE (degrees) | 70.6 / 70.6 | 71.1 / 71.1 | 71.6 / 71.6 | 71.6 / 71.6 | 71.6 / 71.6 | 71.6 / 71.6 |
| FORK OFFSET | 57.5 / 57.5 | 54.5 / 54.5 | 51.5 / 51.5 | 51.5 / 51.5 | 51.5 / 51.5 | 51.5 / 51.5 |
| HEAD TUBE LENGTH | 75 / 75 | 99 / 99 | 122 / 122 | 148 / 148 | 177 / 177 | 203 / 203 |
| BB DROP | 80 / 80 | 80 / 80 | 80 / 80 | 80 / 80 | 78 / 78 | 78 / 78 |
| FRONT CENTER | 584 / 584 | 593 / 593 | 602 / 602 | 619 / 619 | 636 / 636 | 653 / 653 |
| CHAIN STAY LENGTH | 422.5 / 422.5 | 422.5 / 422.5 | 422.5 / 422.5 | 422.5 / 422.5 | 422.5 / 422.5 | 422.5 / 422.5 |
| STANDOVER* | 720 / 720 | 753 / 753 | 779 / 779 | 801 / 801 | 826 / 826 | 851 / 851 |
| WHEELBASE | 993 / 993 | 1002 / 1002 | 1012 / 1012 | 1029 / 1029 | 1047 / 1047 | 1064 / 1064 |
For what might be the first time I’ve ever seen it on a gravel bike, Cervelo says that aero performance has affected its geometry.
More specifically, Cervelo claims that while the Áspero-5 is designed to have ‘stable, confidence-inspiring’ handling with equally-sized tires, the bike is at its most aerodynamic with a 4 mm tire width differential, specifically touting a 40 mm front and a 44 mm rear tire.
With that comes effectively two geometry sheets: one for ‘mixed’ geometry, and one for ‘balanced’ geometry. They’re effectively the same with regard to fit: long and low for a gravel bike, or fairly traditionally standard when coming over from a race road bike. Where the geometry splits is at tube angles. Using the ‘mixed’ geometry steepens the head and seat angles by 0.4 degrees, and changes trail by about 2 mm.
On that note, handling geometry is firmly racey. Wheelbases are on the shorter side for a gravel bike, with a lower bottom bracket and a 422.5 mm chain stay length working across all sizes. It comes awfully close to the latest all-road/endurance bikes like the Specialized Roubaix or the recently launched Cannondale Synapse.
Trail figures are a hand-calculated 63 mm across all sizes with the stock 42 mm tire.
Builds, specs, and pricing
| Build | Drivetrain | Wheelset | Pricing ($/$ CAN/€/£) |
|---|---|---|---|
| Cervelo Áspero-5 Red 1 | SRAM Red AXS/XX Transmission | Reserve 40|44 GR/DT Swiss 240 EXP | $12,500/$16,950/€11,499/£10,000 |
| Cervelo Áspero-5 Force | SRAM Force AXS/X0 Transmission | Reserve 40|44 GR/DT Swiss 350 | $8,700/$11,500/€8,299/£9,000 |
| Cervelo Áspero-5 Frameset | NA | NA | $5,500/$7,500/€5,499/£5,000 |
The Cervelo Áspero-5 is available at launch in two builds and one frameset. Both complete bikes are fairly racey, spec’d with a 48T chainring across sizes. That’s massive compared to the 40 to 42T rings spec’d on most gravel bikes, though they’re matched with a wider-range 10-52t cassette on either size, too.
Interestingly, the Áspero-5 doesn’t come with dedicated gravel tires. Instead, all Áspero-5 builds come with Vittoria Corsa Pro Control road tires in a 42 mm width. That’s not something I’d ride on most gravel terrain, but it’s interesting nonetheless.
Also, all Áspero-5 bikes come spec’d with a ceramic bearing bottom bracket. Good to see.
Pricing is decidedly premium, with the SRAM Force AXS model lining up price-wise with the Specialized Crux, Cannondale SuperX, and Trek Checkmate. It’s also worth mentioning that at least for now, prices haven’t actually increased over the previous-generation bikes.
Riding the Cervelo Áspero-5
There’s no getting around just how focused this Cervelo Áspero-5 gravel bike is on going fast on the smoother, less muddy side of gravel. Everything, from the tires to the frame, to the bars, to the gearing, points toward being a go-fast gravel bike.
In most conditions, the Áspero-5 is a good climber: the fairly vertical seat post means you’re more likely to be over the bottom bracket than not, giving you a powerful climbing position. There’s excellent stiffness from the bottom bracket area too, and so long as the tire hooks up, there’s plenty of performance to be found.
The Áspero-5 feels at its happiest on smooth dirt roads. Chunkiness results in the bike skipping around like most other racey gravel bikes, particularly the Ventum GS1 or Cannondale Super-X. However, I think the Áspero-5 loses a bit to those two bikes because all of that stiffness means this bike doesn’t have quite the comfort you’d hope for to put the power down.
To be fair, that’s not unlike other racey gravel bikes out there. But if you’re looking for a bit more flexibility from the Cervelo family in what terrain you ride, the standard Áspero is the way to go.
Descending is a similar situation. The Áspero-5 has quick handling for a gravel bike, and it requires an attentive rider to get the most speed out of the bike as speeds increase.
I’m a big fan of the gearing idea here, but I can’t help but feel like the 48T chainring choice is optimistic for most gravel riders. I understand the reasoning here: the 48T-52t low combo is roughly similar to a 42T-46t low gear of a SRAM 1×13 XPLR groupset, while the 48T-10t top gear offers good top-end speed. But I can’t help but even the folks looking to go fast on this bike will be better suited to a 46T chainring. At least the Áspero-5 can fit up to a 52T chainring or 2x chainrings should you want it.
The 42 mm Vittoria Corsa Pro Control tires are a decent slick gravel tire. I wholly expected them to flat on my first few times riding the dirt roads and singletrack around here, but they’ve proved durable in my short few weeks with the bike. I still don’t feel quite as confident in these as my preferred gravel slick tires, but they don’t appear as fragile as expected.
Okay, now allow me to indulge as I talk about the Áspero-5 as a road bike, because I think it might be the most interesting road bike I’ve ridden in years.
That lack of grip I complained about became immense grip on tarmac. The stiff ride quality I found for this size 51 cm bike smoothed out and became immediately one of the smoother road bikes I’ve ridden in recent years. The roads I have here, riddled with cracks, potholes, and chip seal, felt much smoother, and I didn’t feel like I lost much speed in most riding conditions. Paired with the sporty fit and handling geometry, I immediately got caught wanting to ride this bike every chance I could get.
This is by no means an endorsement for 42 mm tires as the future of road bikes. But I’ve had more fun with this as a road bike than I have on other road bikes in recent memory.
More to come
We talk constantly about the mountain bike-ification of gravel bikes. More folks than ever want to run a wider tire than what this Cervelo Áspero-5 has to offer, and we’ve already seen the pros at The Traka and Unbound push their tire clearances to the max. The Áspero-5 automatically seems to fall behind.
It leaves me thinking: wouldn’t this have been amazing as a Caledonia-5 rather than as a racey gravel bike? A fast, wide road tire paired with aero frame efficiency and aggressive looks would’ve stunned.
We’ll need to spend more time on the Cervelo Áspero-5, because at first blush, this feels like a fast gravel bike. But as a road bike? This feels like the future.
Gallery
