So an S2 with the new S5 handlebars will beat out an old S5 with normal bars. All other things equal, the S2 gives ~20W advantage over a CAAD in the wind. Who do you race for? 5.5 w/kg is a pretty monstrous number.

Perfect- a 56cm 2015 S5 should fit me well.

Damon,

So 4w of savings so how much faster would an S5 be over an S2 if you did a 40km ride averaging 30 KPH?

Maybe someone else can answer this as my math skills suck.

Most anyone can do 5.5 w/kg. It is more a matter of how long you can sustain 5.5 w/kg.

~15-20 seconds.

Are you sure that's right? 15-20" for 30 kmh and not mph?

Yes, the time saved at slower speeds are actually slightly more than at higher speeds (but less relatively, as you are on the course for a longer time).

5.5 w/kg for an 68kg (150lb) rider is 375w which is in fact a pretty normal 5-15 minute power number for cat 3/4's and closer to FTP for cat 1/2's. For a 140lb rider this is more like 350w which again is not too crazy and common at the end of races. For a top professional that is well over an 1 hour power number. I will admit that aero testing needs to be done at two speeds, one at common finishing speeds (30mph) and another at common cruising speeds (22-24mph) to understand the entire benefits of the bike. I also wish they would explain more clearly (honestly) how crosswinds affect their bikes designs. I live in Kansas and i think i never have a real tail or head wind, its always some weird strong crosswind.

For the most part Mike the CdA of bike stuff is fairly constant at different speeds. So if something reduces your CdA by .01 at 30mph, it will reduce it by .01 at 25mph too.

As for how many watts it saves, you can usually just linearly interpolate. that isn't exact of course but it is real close within 'normal' speeds.

As for crosswinds, that is exactly what yaw angles are all about:
http://www.cervelo.com/...8-7e87cddcd4f6-0.pdf

Page six shows a yaw angle sweep for the old S5 with a rider aboard. Typical cat3 fast people will 90% of the time be under 10deg yaw, but an attack into a nasty crosswind might start seeing 15-20deg

Usually the advantages of well designed aero wheels and frames is higher in a bad crosswind than in a head on or tail wind.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Just wondering if there is goin to be a new Vwd version?
From what you've said the new s5 is similar weight to old vwd how does stiffness of new s5 compare to vwd?
Do you know how soon bar will be available as an individual component?

I like it when people complain about a lack of information on topics that have been covered so many times. Wind tunnel speed scales to 20mph, and yaw can be read about in lots of places. Just because you haven't read it, doesn't mean its not out there.

Hi j, good questions.

The S5 replaces the S5VWD, it's at the same level. There will be no VWD version of this S5. We're just finally extending the name simplification now to the S5 as well as the R-series. No more "Team" or "VWD" versions of anything.

You're right, the new S5 frame is similar weight to the old S5VWD.

The old S5 and S5VWD have about the same BB, lateral and torsional stiffness. Just the VWD is lighter.

The bar is scheduled to be available when the bikes are, which are currently expected roughly in November or so.

Cheers,

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

Not sure how i missed the white paper, then again when you are doing pre-med work you tend to get a bit frazzled mentally and really don't enjoy extra work :) I had incorrectly assumed that the time savings were exponential not linear. I am slowly being convinced that the S5 might be the next purchase.

With all of this talk about aero I got a wild hair up my ass yesterday. I had a Trek TTX 9.9 frame laying around and said, "what the hell", built it up as a road bike, let's see what it can do. I rode it today and I'll be damned. That is the fastest, by far, road bike "so to speak" that I have ever ridden. Riding well below 1 hour power I shattered a 50 mile course record in 1:58, previous record of 2:02 on a road bike with 85deepwheels.I had box rim wheels on the TTX today. I feel like an idiot for not doing something like this earlier. This is amazing.

"Aero is always on!"

Your TTX is especially good as a road bike, because the stack is high and the reach short (for a TT bike).

Just be aware, if you plan to race, most TT frame are UCI illegal as road bikes: the gussets at the joints aren't allowed in road frames.

Cheers,

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

Thanks and I'll be damned...the fastest road bike I'd never ridden was collecting dust. Before this turn of events, I had already decided to get a good aero frame as my next road bike . There's a Cervelo dealer conveniently, 3 miles from my door. Up until now, I had decided on the S3 to be my first aero road bike. After this TTX experiment, why shouldn't I get a P2 and make it a road bike? The geometry on a 54 is quite similar to the Med. TTX. As far as the UCI regs go, (and I appreciate you letting me know) I think, although not certain, that I could race the P2 or TTX in Masters USA cycling events? Thanks again for your feedback!

Correct of course. But the question is, at how many races in North America are UCI rules followed or enforced? From what I have heard (not being a bike racer myself), very few.

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Advanced Aero TopTube Storage for Road, Gravel, & Tri...ZeroSlip & Direct-mount, made in the USA.
DarkSpeedWorks.com.....Reviews.....Insta.....Facebook
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Hi greg,

As Greg (DSW) mentioned below, in the US at least, not many races are actually run under UCI regulations.

When I moved to Canada my eyes were opened: nearly every race is technically under UCI rules, though at the club level they are somewhat overlooked - until championship time. This is more or less the case worldwide; USA is the exception.

So check with your local race representative to be sure.

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

Indeed. :-) (Assuming it fits.)

But why turn the question around: why not just get an S2 and make it a road bike?

Cheers,

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

The S2 will be better overall for a few reasons:

1. vertical dropouts
2. two bottle cages
3. likely better handling as a road bike

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Damon, I've always been curious, have you guys isolated the penalty of having a traditional airfoil (previous S series) on the downtube with standard bottle vs. a truncated airfoil (new S series) (who are we kidding, of course you have, I just want the answer! :D )? It looks like there's decent savings putting the bottle in the lower position (14g claimed in the S5 whitepaper), but what about the above scenario? I'm considering ditching my current road and TT bikes in favor of one aero road bike and just weighing frame options and prioritizing features.

I'm only assuming that your data would suggest that the P2 would be faster than the S2 as a road bike...don't know?
Thanks for all of your feedback !

Thanks Jack!
I don't think that the dropouts would be a problem. Are you thinking pit wheel change in a race situation?
Rarely ever use 2 bottles racing...one in jersey for training would work...or under the seat.
Handling...if it's close to the TTX with road bars and road position..it would be more than adequate. This was probably my biggest reason for never trying this before...in that thinking that the handling would suck.
So riding same wattage side by side with both frames set up equal, in road position, zero wind....would the P2 be faster?

Probably P2 faster
S5 probably near the same

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Only if you think a P2 is as fast as a P4 ;-)

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http://bikeblather.blogspot.com/