Review: The Cervélo R5 Doesn’t Try to Appeal to Everyone, and It’s Better for It

Updated September 5, 2025 05:06PM

We first saw the Cervélo R5 at the Tour de France, and it looked awfully similar to the then-current model. Really, there were only two tell-tale signs of it being a new bike: the inclusion of SRAM UDH (Universal Derailleur Hanger), and a new one-piece handlebar, the first in the R-Series lineup.

As it turns out, there was a whole lot more going on under the skin. How much more? Try 5.97 kg or 13.16 pounds in a size 56 cm frame, claimed. My 51 cm bike was lighter still, at 13 pounds (5.9 kg) on the dot.

But climbing bikes are dead! Aero bikes rule the roost, you all say in unison. While I think there’s some truth to that, Cervélo has continued on with its R5, refining it and narrowing its scope into the lightest bike it could be. And while I’m not entirely convinced everyone should be riding a climbing-centric bike like the R5, there is no denying just how fun a bike like this is to ride.

Quick hits: Seven things to know about the Cervélo R5

The Cervélo R5 is a story of weight savings

The previous generations of the Cervélo R5 (much less the R-series bikes) weren’t pure climbing bikes, at least that’s how Scott Roy, engineering manager of Cervélo, claims they were. Rather, the R-series bikes (including the R5 and the dearly departed R3) were focused on being bikes for The Classics, races like Paris-Roubaix or Milan-San Remo. However, the improvements in weight, ride quality, and overall rideability have focused the R5 on being a climbing bike first and foremost.

And the weight reduction was obsessive on this bike. Cervélo touts that its updates over the previous generation bike – not just the frameset – amount to a claimed 396.5 grams saved over the previous bike. A significant portion of that comes from the frameset, but the handlebars have undergone a weight reduction, as have the wheels and the overall package.

Cervélo said it wanted a bike that was 250 g below the UCI weight limit. A large portion of that is so that Visma-Lease a Bike riders could have a bike that came in at the UCI weight limit with a transponder, but it also allows size 58 cm riders like Matteo Jorgenson to have a ready-to-race bike that comes in at the weight limit.

The weight reduction around the frame doesn’t necessarily come just from a new carbon layup or “higher modulus.” Rather, it comes from greater manufacturing efficiencies. Much of the frame, for example, is physically smaller than before. The downtube got thinner, the head tube got slimmer, and the top tube got flatter, too. The focus on minimizing material where possible results in seat stays that are so thin they only meet the UCI minimum 10 mm x 10 mm tube dimension when painted.

The fork sees similar weight savings. The fork crown is simpler than before, ditching the chin that smoothed the transition between the fork and the frame’s downtube. Cervélo says this saved anything between 8 to 14 g in weight, and they were able to do it without losing any aero performance. The steerer tube brake entry hole molding has been simplified, both adding strength around the lower bit of the steerer tube and saving 5 grams.

The most obvious change to the fork might be the new thru-bolt brake mounts. The mounting system ditches the adaptor mount that most road and gravel bikes use on the fork, replacing it with a pair of bolts fastened opposite the brake caliper. This implementation isn’t new, as bikes like the Salsa Warbird, 3T’s slew of road and gravel bikes, and the outgoing Scott Addict RC have all used this mount to some degree. But Cervélo says this new mount saves as much as 30 grams over a standard fork mounting system, as it doesn’t need alloy slugs molded into the fork.

The weight savings continue to other parts of the bike. A redesigned two-bolt seat post head design saves 23 grams over the outgoing SP 24 seat post, despite using the same basic carbon layup everywhere else. The new headset compression plug saves 9.5 grams, while a new set of bearing caps saves as much as 6 grams. Rather than using Reserve’s free-flowing tubeless valves, the aluminum tubeless valves here save 5.8 grams, and a refined manufacturing process means the new Reserve 34|37 SL wheels save 60 grams, all at the rims.

Even the handlebars have seen a weight reduction. Cervélo claims this new HB18 handlebar saves 134 grams over the outgoing HB13/ST31 handlebar and stem combo. My 38 cm x 90 mm stem one-piece handlebar tipped my scales at just 266 grams, with a 40 cm x 100 mm one-piece bar and stem coming in at a claimed 283 grams.

Perhaps the only concession to the real world is the newly adopted SRAM UDH system, allowing for the use of SRAM direct-mount derailleurs. However, Cervélo has a new hanger called Cervélo eUDH that saves one gram, for a total of 25.5 grams over the standard system.

The grand total is a 100 gram reduction in frame and fork weight, and a 396.5 gram weight savings comparing complete bike builds year over year

Handling remains a focus, not aero

Outside of getting the R5 250 grams under the UCI weight limit, Roy said the other main goal of the bike was explicit:

The reduced surface area from smaller tubes has resulted in a bike that Cervélo claims isn’t really any stiffer a bike than before. There’s a claimed 13 percent increase in bottom bracket stiffness, thanks in part to the flatter and wider top tube. A stiffer fork means the R5 is allowed to have a claimed 8 percent decrease in headtube stiffness. Cervélo says its testing results in an overall system that feels just as stiff as before, with handling and ride quality equivalent to the outgoing bike.

Some of that head tube stiffness comes back at least partially from the new one-piece handlebar, Cervélo’s first on a bike that isn’t the S5. The one-piece system – featuring a 4 cm flare from the hoods to the drops – is never going to be the preferred solution for home mechanics. But there’s no denying the lower weight and improved stiffness that comes with the handlebar.

Like the S5, Cervélo says original buyers will be able to swap their one-piece handlebars for the right dimensions through their dealers for no additional cost.

Conspicuously missing from the list of objectives is to make the bike more aerodynamic. Indeed, Cervélo says the new R5 is only 2 watts faster than the outgoing R5, all thanks to the new one-piece handlebar. And while there hasn’t been back-to-back testing done, the difference between the R5 and S5 at race speeds is “something large,” says Cervélo. There was no clear-cut number here, but a 15-watt split between the two bikes isn’t out of the question.

Geometry

The new Cervélo R5 has ditched the Classics-inspired geometry of the outgoing R5 bikes to adopt geometry that matches the S5 road bike. Visma-Lease a Bike is at least partially responsible for this change, as the team requested the same geometry between the two bikes to ensure its riders can swap between the R5 and S5 without needing to make any fit adjustments.

The big change over the previous generation bikes comes in two places: lower bottom bracket drop, a slightly steeper seat tube angle, and slightly shorter trail figures across the sizes. The bottom bracket drop is largely due to the geometry being designed around a 700c x 29 mm tire, whereas the old bike was designed around a 25 mm tire.

Besides that, the R5 comes in the same six sizes as before. There are still four fork offsets as before, and front center lengths change only marginally.

In short, the latest Cervélo R5 geometry is firmly on the race road bike side of the spectrum. While reach and stack numbers aren’t quite as aggressive as what one might find on the market, I had few issues getting the bars low enough for a racey position.

Riding the Cervélo R5

The trouble with many of these lightweight bikes is that they tend to go all out in the pursuit of low weight, and they end up sacrificing what makes a bike fun to ride. They could lose the responsiveness of the best road bikes, or in the pursuit of stiffness, the ride can become harsh to the point of being uncomfortable to ride quickly. Fortunately, this Cervélo R5 manages to nail both being lightweight and being a great bike to ride.

Yes, the low weight is outstanding. You might use it mostly to impress your friends who were in awe of how narrow the seat stays where, but you feel just how much sharper the bike is on steep pitches of 12 to 15 percent or more. Quick stabs at the pedals are met with immediate acceleration, making this easily one of the most responsive climbing bikes I’ve ridden in some time.

Much of that responsiveness is due to just how light the bike is, but Cervélo using a zero-offset seatpost here really emphasizes the intention to make this a climbing bike. When paired with my size 51 cm bike’s 74 degree seat tube angle and the limited adjustment range of the Prologo saddle, the R5 puts the rider in a position where they have no choice but to stomp on the pedals up a climb.


Size	48	51	54	56	58	61
Stack	496.1	520.2	544.6	567.5	590.7	610.7
Reach	368.7	376.5	383.3	391.1	400.3	408.3
Seat Tube Angle	74.5	74	73.5	73	73	73
Effective TT Length	506	526	544	565	581	595
Head Tube Angle	71	72	73	73	73	73
Fork Offset	57.5	51.5	45.5	45.5	45.5	45.5
Head Tube Length	89.6	109.3	132	156	182.8	203.7
BB Drop	76.5	76.5	74	74	71.5	71.5
Front Centre	579.1	579.9	579.5	594.2	610.8	624.8
Chain Stay Length	410	410	410	410	410	410
Standover*	699.7	731	757.4	779.1	803.4	822.2
Wheelbase	976.8	977.6	978	992.8	1010.3	1024.5

Fortunately, the low weight doesn’t mean the R5 sacrifices in handling. It’s a joy to pilot down a technical descent. The bike’s sharp handling makes it easy to make mid-corner adjustments without much issue, while the chassis has plenty of stiffness to really lean into the corners without feeling the bike move around under you. I generally prefer a bit more trail on a climbing bike (like that of the BMC Teammachine SLR 01) to provide just a bit more high-speed stability, but there’s plenty to like here with the R5.

I’m by no means a sprinter, but I found my size 51 cm Cervélo R5 to be adequately stiff in a sprint. There is hardly any twist in the front end, and sprinting from the drops feels stout and sturdy enough, too. I did find the rear end of the bike wanted to skip around in a sprint on occasion, but I’ll chalk that up to my mediocre sprint form. A swap from the stock 26 mm tire to a 30 mm tire certainly helped add some traction.

I don’t expect these climbing bikes, particularly the ones that forsake aero efficiency, to have the audience of most other race road bikes. Aero advantages compound the faster you go, and for me, the numbers say an aero-focused bike is going to be faster in nearly every ride I have locally. But damn if this Cervélo R5 isn’t an extremely fun bike to ride.

The rest of the build kit is excellent, as you’d expect

As mentioned, the rest of the Cervélo R5 build kit focuses on shaving as much weight as possible. And while that makes this an expensive bike, there aren’t really any compromises made here. Well, mostly.

A Shimano Dura-Ace-equipped bike is going to work magnificently, as one might expect. But while we’re coming up on four and a half years of Shimano Dura-Ace R9200, this groupset is still excellent on all counts. I still think Dura-Ace has the smoothest shifts of any derailleur-driven groupset out there, both at the front and the back. And while I’ve come to prefer the braking and hood ergonomics of the latest SRAM groupsets, Dura-Ace still offers phenomenal braking power and good comfort.

I’m a big fan of Cervélo’s new HB18 handlebars. I appreciate the flare from the hoods to the drops, allowing riders to have a fairly narrow (and aero position) in the hoods, with a bit more width down below for greater control and leverage in a sprint. And despite the low weight, I never once felt the bars lacked for stiffness.

I should note here that the HB18 bars are compatible with Cervélo’s existing internal cable routing spacer system, allowing folks to put this on everything from the Aspero-5 to the Caledonia-5 without issue. It’s also compatible with Cervélo’s accessory and computer mount system, the latter of which I couldn’t get tight enough to hold my bike computer without slipping down. It’s the first time I’ve had this issue among the slew of Cervélo bikes we’ve tested, however, so I’ll call this a one-off issue that, while frustrating, is easy enough to solve.

The new Reserve 34|37 SL wheels make sense on this new R5. They’re seriously light (1170 g on my scale with rim tape) for a wheel that uses steel spokes. A swap to a mid-depth wheelset added a pleasing amount of stiffness to the bike, however. If the R5 were my main road bike, I’d swap for something deeper to add a bit more precision to the handling.

The Reserve wheels are wrapped in 26 mm wide Vittoria Corsa Pro Speed tires. They’re light and no doubt fast in the right conditions. But considering the bike geometry is designed around a 29 mm tire, I’d swap them immediately for something wider. The 30 mm wide Continental Archetype is an excellent pairing in my experience, though any 28-32 mm top-end road tire will only add to the R5’s performance chops.

The Prologo Nago R4 PAS Nack saddle is a comfortable choice here, pleasingly light, and offers decent fore-aft adjustability. There’s little to complain about here, though I did wish I could get the saddle just a bit farther back.

Living with the Cervélo R5

There’s little here with this new Cervélo R5 that would give a long-term owner or home mechanic pause. Really, I don’t think this R5 is any different from most other road bikes I’ve built in recent memory. While I wish the R5 were easier for a home mechanic to maintain, it is roughly the same as you’d find from the rest of the competition here.

The R5 uses a BBRight press fit bottom bracket, as does the Cervélo S5. While I’d much prefer to see a threaded system here to make replacements easier for home mechanics, Cervélo specs a CeramicSpeed SL bottom bracket for this Dura-Ace build. That should make bearing replacements less frequent in the future, besides whatever (very) marginal performance gains might come from a ceramic bottom bracket.

Like most other Cervélo drop bar bikes, the R5 has a proprietary D-shaped steerer tube. It’s nominally a 1 ⅛-inch system, allowing riders to use whatever standard round stem clamp you’d want to. You’ll likely need to get creative with spacers should you use a non-Cervélo stem, but I have little to complain about here that I wouldn’t with any other high-end road bike.

The seat post wedge system has been updated slightly here, with the frame adding shoulders that help hold the wedge in place to prevent creaking. I never heard a squeak or creak from my time with the bike.

I appreciate Cervélo adding a SRAM UDH (Universal Derailleur Hanger) here. The system is far from fault-free, but I appreciate being able to go to any bike shop and theoretically walk out with a derailleur hanger I know will work for my bike. The system is heavier than a proprietary one Cervélo could’ve designed, but it’s a system I’m happy is here.

I should also note that outside of the computer mount not staying in place under a proper torque rating, Cervélo does a good job with finishes here. As one might expect for the price, everything here fits together nicely, is easy to use, and feels high quality.

Cervélo R5 vs the competition

All of these bikes feel relatively similar, at least in my experience. The current Specialized Aethos lacks the stiffness of these other bikes, particularly in the front end, and you feel that most in a sprint. The TCR, Orca, and Teammachine SLR 01 all feel fairly similar. The TCR felt the sharpest of the bunch, thanks at least partially to the Cadex MAX 40 wheels with carbon spokes. The Orca and Teammachine SLR 01 are both more mild-mannered amongst other race road bikes on the market.

The Cervélo R5 hews closer to the TCR in my experience riding a size 51 cm bike. Add a wheelset with carbon spokes, and all of the sharpness of the R5 is elevated, from its turn-in to its acceleration. I’ve found plenty of front-end stiffness with the R5 as well, though in my limited time on the bike, the Teammachine and TCR were likely ever so slightly stiffer up front than the R5.

Of course, there’s also the Scott Addict RC, one of the few off-the-shelf bikes to match (and outright beat) the Cervélo R5’s claimed weight. The frame and fork weights are nearly the same between the two bikes, both in rarified air. However, I haven’t ridden that new bike myself, and I reckon that bike is already as light – or as stiff-riding – as it’ll get out of the box.

Conclusion

Cervélo says its obsession with weight resulted in the R5 admittedly having the narrowest appeal of any of Cervélo’s road bikes. I would agree with this assessment; the R5 is not going to be for everyone. Its price is too high for folks who might benefit most from a lightweight bike, and the focus on weight makes too many compromises for folks who want the fastest solution the majority of the time.

That said, there are a few road bikes I’ve enjoyed riding this past year as much as I have this Cervélo R5. The low weight, superb handling, and balanced ride quality make for a bike that is a joy to ride, even if it isn’t the fastest in most situations. Add in Cervélo’s work to make this bike as light as possible, and it’s a bike that has a story to match. There are intriguing engineering stories across all of these high-end bikes, but few are quite as interesting as this latest R5.

It’s a bike that makes me wish Cervélo offered a more affordable option, so that more folks could experience just how fun this bike is. Time to get to work, Cervélo, because all the goodness here deserves to be shared amongst the lineup.