Updated – EB14: Cervelo Ups the Aero Road Ante Again with a New S5, plus Updated RCA

Cervelo_New_S5_complete_aero_road_bike_new_Cockpit Cervelo_New_RCA_light_road_bike_Bear

After almost universal accolades from the cycling media for the previous generation of the S5 as possibly the fastest road bike on the market, including our own, instead of taking it as a compliment, Cervélo took it as a challenge to make the bike even faster. What resulted is a new bike that chops another 21.3 watts off from the last S5 VWD.

At the same time for the RCA, Cervélo went back to the drawing board to see how they could make their handmade super bike an even better all-arounder, and where they could make measurable weight gains.

Read on for full details on the S5 and the lowdown on the new RCA…

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Cervélo establishes a set of design priorities as they develop each of their bike lines, and with the S-series it goes: 1. Aerodynamics, 2. Stiffness, 3. Weight, then 4. System Thinking. One of the System Thinking approaches applies to aerodynamics, so through CFD Cervélo studied the impacts of individual bike elements on the total aero drag of a road bike with its rider. The numbers revealed key elements that had major effects, and these were items where they dove into more deeply to minimize drag:

  • 1% – seatpost
  • 2% – rear brake
  • 3% – front brakw
  • 5% – rear wheel
  • 9% – drivetrain
  • 9% – bottle
  • 9% – fork
  • 16% – frame
  • 16% – front wheel
  • 30% – handlebar

The primary focus of the S5 being aerodynamics, Cervélo put a lot of work into making sure their off-the-shelf bike remained an aero market leader. The did this by lowering the downtube even more and smoothing the transition as it drops to meet the fork, reshaping the already truncated downtube to accommodate the real world inclusion of water bottles, reworking and smoothing the transitions from the headtube down across the lower headset bearing and down the fork, slightly extending the seat tube cutout, and reshaping the seatstay cluster to better shield the rear brake.

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Aerodynamics also improve through the use of new aero components. First, a new single position aero post for the first time will be interchangeable with the S5 and S3. A 2-position post will also be available to push a more forward position (and will be included with the 48cm frame to accommodate the fit of smaller riders.) More of a surprise is the inclusion of a new all carbon Cervélo Aero handlebar. The new bar is the result of a happy medium design between an all out crazy bar and a conventional approach. The end result is a 270g (at 42cm; 80mm reach/128mm drop) shaped bar with double inboard cable routing that saves 4.4Watts over a round bar in the wind tunnel and still includes a standard 31.8 clamp. The bar will come on all three S5 models, and will be available separately for $400 from the beginning of October. (Other market prices and availability are yet to be announced.)

Update: We spoke again with Cervélo about the Aero handlebar, and even though it appears to grossly exceed the 3:1 rule, it has been specifically checked over with the UCI, and has been approved for road use!

Cervelo_New_S5_complete_aero_road_bike_Aero_Road_Bars_top_view

The second element was the stiffness, where it was an immediate requirement to maximize stiffness while not compromising on weight. By generally increasing the widths of tubing sections overall and optimizing material application, a major increase of 35% in headtube stiffness and 17% fork lateral stiffness was achieved, bringing the aero road bike into the performance realm of modern round-tube rod bikes. These major improvements were also supported by new manufacturing techniques that led to better put together frames, and upsized constructions like overall bigger BBright bottom bracket shapes and a 1 3/8″ lower headset bearing. The third element come directly from optimizing construction for a marginal weight reduction.

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System Thinking gets even bigger into a usability perspective with features like future-proof cable routing, customer feedback leading to a 2cm reduction in stack vs. the last version, and an overall increase in attention to detail. The bike’s fork now allows 360° rotation, internal or external Di2 battery mounting, a simpler and more serviceable rear brake attachment, keyed seatpost binder, and straight shot cable routing. Tire clearance is a place where there is big improvement over previous versions. With the 26mm wide HED wheels spec’d on the Dura-Ace bikes, there is clearance for 25mm and (slightly) bigger tires.

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Bikes get spec’d with partner Shimano drivetrains, Rotor cranksets, and HED wheels. The Dura-Ace Di2 version will retail for $10,500, Dura-Ace mechanical for $8500, Ultegra mechanical for $5500, and a frameset for $4500.

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With the handmade attention to detail of the RCA, Cervélo won Eurobike Gold last year, and continues to refine their top of the line frameset. New highlights with the newest version are reduced overall weight, improved durability, and slightly more availability. With the RCA as Cervélo’s ultimate road bike, design priorities are Weight, Stiffness, then Ride Quality.

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The frame now weighs in at 670g (54cm w/ all aluminum hardware included) for an actual weight gain of ~3g from last year’s model. The added weight comes from boosts in durabilty and ride quality with the addition of the 1 1/8″ – 1 3/8″ headset, future-proof internal cable routing, as well as reinforced tubing throughout in places that were previously susceptible to damage during regular use (read: sitting on the toptube, crashing, leaning/dropping the bike on its side, etc.) It is actually impressive that frame weight didn’t increase when you see the success Cervélo had with independently isolating the longitudinal (front to back) stiffness from lateral (side to side) stiffness. They were able to do this in large part by refining the specific placement and reducing excess overlap of individual carbon layers, with a result of +15% lateral and -7% longitudinal stiffness for an overall more lively yet efficient ride. They were able to increase the performance almost exclusively through the development of new production methods that can only be carried out at the low production, hands-on levels of the CA facility.

Cervelo_New_RCA_light_road_bike_Frameset

The biggest improvement by far though was the redesign of the fork and its move to the RCA production. The fork itslef is now just 277g, for a weight savings of 35g since the last iteration. The fork is one of the first from Cervélo to bring back a slightly curved fork blade to improve ride quality and bump absorption. Two of the main areas where weight was saved were in the inclusion of ultra high modulus fibers that could now run continuously up into the steerer as a result of the tapered bearing seat, and in the application of the much lighter, RCA high paint standard.

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The bike will be sold only as a frameset for $10,000. The very time consuming handmade production will still limit overall availability (Cervélo can only produce about 1 frame per day in their California Criterion facility.) But unlike last year it will not be a limited addition, so production will roll ahead as long as cyclists are willing to spend the big bucks. In the words of Cervélo get your order in ‘early and often.’

Cervelo.com

Comments

mudrock - 08/27/14 - 8:54pm

So the previous iteration of the RCA could be damaged by sitting on the toptube or having a gust of wind knock it over while getting your coffee? And it cost 10 grand?

Guy - 08/27/14 - 9:03pm

That’s what I gathered too.

Rico - 08/27/14 - 9:29pm

The S5 looks good in size Small – let’s see a 58 and see if it still has that monster head tube area.

Rico - 08/27/14 - 9:30pm

If they improved that I may consider buying one, it looks great with the color layout as well.

John - 08/27/14 - 9:49pm

Yeah, good luck getting those frames warrantied.

Also, since wider tires are the new normal, why is it like pulling teeth to get manufacturers to design enough clearance for 25s, let alone 28s?

WV Cycling - 08/27/14 - 9:56pm

I don’t think I could trust a 277g fork, no matter who made it.

Ralph! - 08/27/14 - 11:59pm

I hope the new S5 rides better than the old S5. I found that bike to be really stiff in the front and really stiff in the back but instead of using carbon for the the top tube they used a wet noodle. It creates the effect of the front and rear of the bike not being connected together. Blah.

edi - 08/28/14 - 2:15am

I hope that now is also possible to mount campagnolo eps v2 battery inside the frame!!!

Permon - 08/28/14 - 4:40am

to Ralph: +1

Sam - 08/28/14 - 7:08am

“customer feedback leading to a 2cm reduction in stack vs. the last version”

Do you have a new geometry chart?

jm - 08/28/14 - 8:17am

@ ralph! & permon
The old S5 rides WAY better then you say. it’s 100 times a better riding bike the the S-works Venge, and I have owned both. Stiffer, faster, more comfortable, lighter and cheaper.

@ John, sound like you have a really crappy Cervelo dealer who is not in good standing with the company. My LBS has had no problem with warranty issues, and even crash replacement upgrades.

Just a reminder a new R5 54cm weighs 817G with all hardware and an alloy seat-post collar, on my personal scale.

Kyle - 08/28/14 - 9:03am

Why isn’t anyone talking about the mis-molded BB shells on the R-5s?

Rick - 08/28/14 - 10:42am

@ mudrock. You are not supposed to sit on the top tube, you are supposed to sit on the saddle.

@ kyle. That’s not mis-molded, its called BBRight. go to http://www.bbright.net and click the “why bbright” link and it will show you how/why they sized it like that.

@ jm. +1

Von Kruiser - 08/28/14 - 12:26pm

Everyone now has a Garmin on top of their bar… so your advantage of any aero design in the bar is thrown out the window… as well as the high price you pay.

Psi Squared - 08/28/14 - 2:42pm

@Von Kruiser: no. An aero bar with a Garmin on top or in front is still likely more aero than a non-aero bar with a Garmin on top or in front.

MMC - 08/28/14 - 3:55pm

Sorry Cervelo but that bar looks absolutely stupid. Why not just produce a once piece bar ala’ Cinelli Ram.
If your answer is you don’t want to bother with diff molds to suit stem lengths then that’s just pure cop-out.

Permon - 08/28/14 - 4:50pm

to MMC: it is not a stupid idea! Definatelly not! This solution let You set the angle of the handlebar the way You prefer. And it is not only about lenght of stem when considering molds….. you also need to consider different width for handlebars and different angles of stems! So, there is a lot of possible variations…..no producer wants to deal with such a mess! Maybe some large companies like FSA, Specialized, 3T can do it….but Cervelo? Would You buy Cervelo “combo” for Your bike? NO!

John - 08/28/14 - 6:44pm

@VonKruiser: Cervelo is telling BikeRadar those bars are more aero with a Garmin on top: http://www.bikeradar.com/us/road/news/article/cervelo-s5-aero-road-bike-relaunched-for-2015-42254/

Rico - 08/28/14 - 7:07pm

If they dropped the stack 2cm this frame is starting to look really good to me. I missed that info in the first read/scan. So sick of using slammed -17 stems on all the bikes that fit me otherwise.

Dan - 08/28/14 - 7:11pm

I have ridden a lot of bikes and the old S5 was the worst handling bike I have every ridden. It didn’t climb, turn or descend well, but if you just wanted to motor in a straight line this was your bike.

James Price - 08/28/14 - 10:02pm

Agree with the statement that the first generation S5 didn’t handle well, just felt disjointed. and it was 200 or so grams heavier than my venue.
This one SOUNDS as if it may close the gap on a lot of areas where it didn’t measure up, though, and increase its lead in the main one where it was ahead, aerodynamics.
But really, I can’t buy the claim it cuts 21.3 watts from the previous one, which was a pretty slick item. That’s got to be getting close to the entire drag the old frame generates at speed.
I mean, lets just be logical here. Look at the head on photo. they say they got 4 watts out of the bars. And the bars are a major part of what’s presented to the wind here.
Bike looks nice though. And the bars, too. want a set of those, but then you have to start thinking, 1) is UCI going to reverse itself and 2), where do I put the garmin now so as not to spoil that $400 aero gain.

Macen - 08/29/14 - 1:00pm

I think there was a typo on the 21.3 number. Another article I read stated it saved 21.3 grams of drag which is roughly 2.13 watts (rule of thumb is 10 grams of drag for every watt). Regarding the arguement about using an integrated bar/stem combo, those are typically not economically feasible on a small scale production plan. The molds alone cost between $10000 and $25000 a piece. And when you consider the broad range of bar widths, stem lengths, and stem angles required to fit a workable range of riders, you would end up with a massive amount of overhead that you will probably never recoup. And Cervelo may find that they can make some improvements to their bar in the future. Scraping $40000 in molds versus $250000 is a much easier pill to swallow.

DT - 08/29/14 - 8:13pm

@Permon +1
Yeah stems are possibly THE most changed part for fitting. Important, v. customer cost-effective and practical. Thus the separate bar/stem.

Cory Benson - 08/29/14 - 8:29pm

The watts number is correct as straight from Cervelo. Their 2015 product data quotes 22W, but the presentation at the bikes release listed 21.3W.

Joelrides - 08/29/14 - 10:30pm

The RCA color scheme reminds me of the black Niner RLT 9.

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