Hi tri,

The post isn't reversible, but the shaft is the same shape as the old S5 (and new S3 and new S2), so now all current S-series can swap posts - including the 2-position post. All posts are available after market, but if you know someone with one they might swap you for your single-position post.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Damon,
Are headtube sizes (and stack) lower than current S5 as stated on some websites?
Pictured bike does not look low stack though I do not know what size it is.
I am hoping not-

Hi Orbilius,

As you can imagine, we benchmarked a bunch of aero road bars (including that one) and ours was the fastest.

I also have a Vuka Sprint and I like it a lot, it's a great bar.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi BMANX,

We considered clip ons, but the mission for this bar was pure road. Adding holes subtracts strength, which requires reinforcements, which add more weight back again...

I've seen other aero drap bars that *are* clip-on compatible though. They'd fit your request perfectly I'd think.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi just,

Might be a typo or mis-communication there; we've weighed one at 1065 grams. Easy to get confused though, we also introduced the new Rca with lots of numbers as well.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Equal.

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Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Correct. And you can get the bar aftermarket, so if you want one for your SLC-SL, go for it! :-)

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi dj,

The frame stack is lower by between ~1 cm (size 48) to ~2 cm (size 61). Size 56 is ~1.5 cm lower stack. (I'm not in the office right now, so these numbers are from memory, but they're closer than the other number.)

The ~22 mm quoted is the difference in head tube length. Unfortunately, that crept into our presentation, even though the fork lengths are 6 mm different, which makes differences in HT lengths much less useful.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Where's the "like" button when you need it.

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

I loved that post! Can you find a link?

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi dj,

Yes, exactly.

We've been thinking of ways to make stack & reach more intuitive. Turns out, by coincidence, the stack of a typical classic lugged steel frame is about the same as it's centre-to-centre seat tube length. Usually. Might help people get a "feel" for stack at least. It's still not perfect though.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

So the frame is stiffer, takes bigger tires, but equally aero to the current S5. So the 21.3 watt improvement is entirely due to handlebars and wheels?

---

Suffer Well.

Hi great,

21.3 Watts savings*

*at 40 km/h

Fixed it for you.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi Nigel, Yes, it's not easy to get the meaning, but you nailed it. And the numbers are from an S5 with rider and normal drop bars.



Good thinking, but we normalize Foam Dave's position, so in this case a rider who wants to go lower might expect another incremental improvement.



Very good summary. Thanks for the compliments, and I'll pass them along to the design team.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi dj,

We've lumped brake levers in with the bars. I'm wishing now we'd labelled it that way, but we'd been so used to it ourselves we didn't notice.

And the CFD analysis includes the rider (so as you said, hands cover some of the drops).

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Thanks for making that comparison dj. It matches our test results.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi bootsie,

Stack is lower, but not as much as has been previously stated. See my earlier post for my best memory, but when the bike is available (planned for October) we'll put the web page up, including the geometry chart with all the real dimensions.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Hi jmh,

Exactly.

Cheers,

---

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Damon. Thanks for the responses. Much appreciated.

---

Suffer Well.

Is there any improvement in ride compliance or rear end stiffness? Trying to figure out upgrading from a current S5 with aero drop bars is worth it.

Also is there anyway to mount a Garmin to the front of the bars, similar to an out front mount?

Thanks for the clarification about stack. Out of interest, is this change due to Cervelo deciding that their previous stack philosophy for the S series was wrong, or that the customer is wrong but Cervelo has decided to give them what they have been asking for anyway?* Further, if the new geometry results in an extra 1.5 cm of spacers below the stem how much aero cost is associated with that? How can that cost be minimized? Might seem like aero nitpicking but that's what this bike is all about.

*It seems to me that this is all somehow related to the lost art of riding in the drops. This leads me to another question I've been pondering for a while. Used to be that road bars were fairly high and pros would ride in the drops with a good bend at the elbow in order to get low. Now with this fashion for slammed stems you see many road pros riding in the drops with their arms totally straight. In other words their hands are lower but the position of their body and heads maybe not. Based on frontal area seems the former would be more aero but has anyone tested this - same body position for different bar heights/elbow bends? Something for Mark Cote and the #aeroiseverything guys?

For visibility I prefer my Garmin out in front but FWIW according to this there's even an aero benefit of putting the Garmin on the stem with the new Cervelo road bars.

Damon, how much "slower," recognizing it's all relative, would my '09 S2 with the new aero bar be compared to the new S5? Also, when is Cervelo going to come out with a cyclocross bike?

New geo chart http://brimages.bikeboardmedia.netdna-cdn.com/...geometry-600x492.jpg

Thanks, Damon, for the great info! I keep waiting for Cervelo to come out with a version of your cantilever bike.

Question: when stack is reduced, is that along a 73 degree angle, equivalent to spacer differences? This would be my guess, because then existing customers can use the same size frame with a spacer stack difference. This will increase reach, the ratio the cotangent of 73 degrees, or 30.6%. Alternatively, you could keep reach constant. This would shift the bars down, but not forward. Restoring geometry would then require a combination of spacers, stem flip, and stem length change. Lowering the bars typically requires a reach reduction, not increase, for a given rider with a given pack position, so I'm guessing the fixed stack approach may be preferred, but the increased reach approach was taken for pragmatic reasons. Just a guess.