Campag4life

Hard to believe of all the riders for input, Cavendish would matter. Likely a 15 y.o. girl could beat him arm wrestling. Of all the sprinters in the peloton, he is the weakest and his watt nos. are the lowest. Hard to believe that Kittel or Greipel who probably put out 30% more watts at full flight than Dish can make due with a conventional stem...or Boonen or anybody else that has ever put out 2000 watts. Reason why Cavendish can compete is because he is the size of an ant.
Sorry to be skeptical. For the amateur, too stiff is more of a scourge than not stiff enough.

Campag4life

Dean and HT,
Minute indeed,
Truthfully drag nos. are nothing compared to the '2014' S5. Minutia. Just buy the 2014 S5 and call it good which btw is a great bike with decent ride unlike the Gen 1. Gen II S3 is a great bang for buck aero bike as well. Put the rest in Jr's college fund.

Straight ahead aka 0 deg yaw, Y-wing versus conventional stem is the same. Graph below. Only at yaw aka 'sail effect' is there 'any' difference which is still nebulous at '30 mph'. Air drag goes up by the 'square' of speed. Truthfully, that is why they perform the test at 30 mph even though it is a speed few riders reach in a ride or race unless descending...or unless a world class cyclist for brief periods in their own air. 30 mph magnifies the drag difference because drag increases by the S^2.
Reason yaw drag exists at all is the difference of lateral surface area of a conventional stem...this marginal surface area versus the Y-wing spars with reduced surface area in profile. Straight ahead there is literally nothing between the stem types. No difference.

PS: All said, to me bang for buck, few 2 year old race bikes offer the value of a barely used Gen II Cervelo S3. I have been casually on the lookout for one for a while but haven't found the groupset/wheelset combo I would prefer. Just casually looking. I like the bike and its a great value. Cervelo addressed many typical aero bike flaws with the Gen II released in 2014 as discussed. The Gen I was a much more rough riding bike...Cervelo's first soirée but Cervelo was really on the forefront of aero bike design as many know as lots of old Solist's still riding around...rough ride and all.

The following video is perhaps the best review on the web I have read exposing the flaws of the Gen II bike. This young man really understands bicycles. Very knowledgeable Englishman. He pans front end stiffness of the bike which btw is not a huge deal to me because I am not a great sprinter and for me at least I welcome a bit more give or compliance in the front. BBright BB is massive...perhaps to a fault compromising tire room on the drive side as stated. Also Cervelo introduced spaghetti straps for seat stays for rear end compliance and has speculated before that these can be chopped off the bike and it will still support the rider because the chainstays are so massive for power transmission. And then there is the horrific indexed single saddle clamp bolt design. Reviewer was spot on. Cervelo has offered 2 bolt designs in the past...buddy of mine has an older carbon Soloist with 2 bolt and it is so much better.

But still love the bike replete with its flaws or rather design tradeoffs Cervelo engineers decided upon...robbing Peter to pay Paul.
Love the shape and geometry, rides pretty well and the geometry isn't as back breaking as some aero bikes.
Enjoy the video. Quite illuminating:

Also, here is a 2019 S5 Disc review for those interested. This may change some minds about the bike. Looks nice in the video:

Dean V

It will also be heavier.
Bike weight is something that seems to be glossed over nowadays with disc brake bikes.
The reviewers seem to be onboard with this too as they rarely mention weight now.

Campag4life

Yes, the '19 S5 Disc bike sure isn't a climbing bike. 17.5 lbs with Ultegra Di2 as noted by the new owner. Not exactly light for sure.
Historically, aero bikes aren't light but one would think they could have brought in the new S5 a bit lower. Not sure if frameset weight is available on the web for the new bike.
Aero versus weight, pick one.

Dean, you own a lot of nice high end bikes. You say you ride your Al TCR the most or a lot. Of course the TCR is one of the best race bikes on the planet and some even give it the nod over the venerable Tarmac. Do you have a favorite out of your collection?

Dean V

I don't really have a favourite. They are all a bit different to each other and it is nice to have a bit of variety.
For example the Domane is the most comfortable but often it is nice to ride a lighter bike with narrower tyres and a bit more "zing".
In fact contrary to the current trend for "comfort" on a bike I will only choose the Trek if the ride involves a bit of gravel as that comfort comes at the expense of being a duller ride.
Something like a TCR is still plenty comfortable enough.
I also have a bike made from Reynolds 953 by a local frame builder that I like a lot.

Campag4life

Thanks. To me, you have great wisdom about bikes. Some people at the end of the day and many performance cyclists don't want to ride a Lincoln but rather a Porsche.
They want to feel that connection to the road and not isolated from it. Of course, on group rides over the rough stuff on the road at speed, sometimes we wish for a bit more isolation. It can vary on a ride.

But if you think about why people choose an aero bike...like a Cervelo S-series or a Venge or a Madone, it ain't about comfort, it ain't about weight, its about cutting the wind and pure speed. Some and not all riders will accept some sacrifice to ride and weight penalty in pursuit of less watts per mph on the flat.

Another good GCN video comparing aero versus climbing bike:

And insightful video from relative new comer to GCN, ex-pro Emma investigating the blurred line of what the pros ride. Listen to the Giant mechanic. They choose the TCR versus the more aero Propel in most cases. Rider feel still matters...as likely feel affects watt production over the long haul in the GC. And another unexpected comment came from the Cervelo rep who stated that their rides preferred the S5 to R5 for ride quality. Now that is a twist. Its been written before that the S-series has stolen sales from the R because Cervelo really improved ride quality for the S in 2014 for the gen II. Presume the Gen III is if anything even better.

PS: pretty sure Emma's personal bike is a Trek Emonda. Lastly, perhaps the biggest twist of all in what bike to choose was the 2016 winner of the Paris Roubaix. Arguable the most grueling of all bike races wasn't won on a custom endurance bike like it has been in the past and present but rather on a second generation Scott Foil. Mathew Hayman is an ironman beyond a doubt. Keep in mind, he can ride whatever he wants on the cobbles and yet chose that bike. First gen Scott Foil was one of the stiffest aero bikes ever produced. Sure the Swiss company Scott improved the ride for the second gen Foil but the angles and geometry are a far cry from an endurance bike designed for the rough stuff. For every rule, there is an exception.
https://www.cyclingnews.com/news/meet...-foil-gallery/