Just reading the Cervelo claim on the new S5. It may be more slippery, but I find the drag reduction a bit hard to believe. 9.9 watts or 92 grams of drag: really? Do you know how much harder you have to train to get that kind of power increase? It also equates to a big change in position; if you modify your TT position to lose 100g of drag, you will be going a lot faster and have a pretty decent adjustment to make. Compare that to the claims of savings when compared to an already aero S3 frame with a narrow profile. Like some other aero claims, it just seems “too good to be true”.
I know that when I did a TT recently, and a teammate of mine compared power with me (he has a better position, same model bike); we found out that our power is about the same, but he regularly puts 20 seconds into me in the weekly 7-mile TT. Recently, he had his 50mm deep Ritchey front wheel, and I had a Stinger 7, which is 140g of drag less at a yaw of 12.5 degrees. Comparing power, we were still within 2 watts of each other, but my “140g of drag savings” didn’t change the fact that he beat me by the usual 20 seconds (140g of savings should translate into 16s of time savings). It doesn’t directly correlate to the S5 claim, but just shows me that those claims should be taken with a grain of salt. I don’t doubt that my Stinger 7 is faster than his wheel, but a few seconds at best.
Just reading the Cervelo claim on the new S5. It may be more slippery, but I find the drag reduction a bit hard to believe. 9.9 watts or 92 grams of drag: really?
Yes. Really.
Do you know how much harder you have to train to get that kind of power increase?
Yes…painfully so…
It also equates to a big change in position; if you modify your TT position to lose 100g of drag, you will be going a lot faster and have a pretty decent adjustment to make. Compare that to the claims of savings when compared to an already aero S3 frame with a narrow profile. Like some other aero claims, it just seems “too good to be true”.
I know that when I did a TT recently, and a teammate of mine compared power with me (he has a better position, same model bike); we found out that our power is about the same, but he regularly puts 20 seconds into me in the weekly 7-mile TT. Recently, he had his 50mm deep Ritchey front wheel, and I had a Stinger 7, which is 140g of drag less at a yaw of 12.5 degrees. Comparing power, we were still within 2 watts of each other, but my “140g of drag savings” didn’t change the fact that he beat me by the usual 20 seconds (140g of savings should translate into 16s of time savings). It doesn’t directly correlate to the S5 claim, but just shows me that those claims should be taken with a grain of salt. I don’t doubt that my Stinger 7 is faster than his wheel, but a few seconds at best.
I think what you describe above says more about the rigor of your testing protocol (or, lack thereof) than anything else.
Seriously…100g of drag reduction isn’t really that much to find…heck, I found 1.5X to 2X that amount when testing a P2K vs. a P3…
that test you did - did you keep the tire and tube exactly the same?
its possible that you put a faster wheel on and a slower tire at the same time
but more likely is you aren’t doing careful enough testing to detect 150g difference anyway.
anyway yes I believe it is at least possible that it is 9.9 watts faster. I believe this because when I see obvious results materialize when I combine a dozen or so small claims like this at one time.
(that is to say, I am a LOT faster when I pay attention to a dozen small details, none of which you could notice by itself)
so at least some aero gimmicks are working =)
Just reading the Cervelo claim on the new S5. It may be more slippery, but I find the drag reduction a bit hard to believe. 9.9 watts or 92 grams of drag: really? Do you know how much harder you have to train to get that kind of power increase? It also equates to a big change in position; if you modify your TT position to lose 100g of drag, you will be going a lot faster and have a pretty decent adjustment to make. Compare that to the claims of savings when compared to an already aero S3 frame with a narrow profile. Like some other aero claims, it just seems “too good to be true”.
I know that when I did a TT recently, and a teammate of mine compared power with me (he has a better position, same model bike); we found out that our power is about the same, but he regularly puts 20 seconds into me in the weekly 7-mile TT. Recently, he had his 50mm deep Ritchey front wheel, and I had a Stinger 7, which is 140g of drag less at a yaw of 12.5 degrees. Comparing power, we were still within 2 watts of each other, but my “140g of drag savings” didn’t change the fact that he beat me by the usual 20 seconds (140g of savings should translate into 16s of time savings). It doesn’t directly correlate to the S5 claim, but just shows me that those claims should be taken with a grain of salt. I don’t doubt that my Stinger 7 is faster than his wheel, but a few seconds at best.
My recent P3 to P4 upgrade is showing exactly the gains I would expect to see based on Cervelo’s claims. Same componests and position. Only change was the frame.
I expect the same out of my soon to arrive white S5.
Just reading the Cervelo claim on the new S5. It may be more slippery, but I find the drag reduction a bit hard to believe. 9.9 watts or 92 grams of drag: really? Do you know how much harder you have to train to get that kind of power increase? It also equates to a big change in position; if you modify your TT position to lose 100g of drag, you will be going a lot faster and have a pretty decent adjustment to make. Compare that to the claims of savings when compared to an already aero S3 frame with a narrow profile. Like some other aero claims, it just seems “too good to be true”.
I know that when I did a TT recently, and a teammate of mine compared power with me (he has a better position, same model bike); we found out that our power is about the same, but he regularly puts 20 seconds into me in the weekly 7-mile TT. Recently, he had his 50mm deep Ritchey front wheel, and I had a Stinger 7, which is 140g of drag less at a yaw of 12.5 degrees. Comparing power, we were still within 2 watts of each other, but my “140g of drag savings” didn’t change the fact that he beat me by the usual 20 seconds (140g of savings should translate into 16s of time savings). It doesn’t directly correlate to the S5 claim, but just shows me that those claims should be taken with a grain of salt. I don’t doubt that my Stinger 7 is faster than his wheel, but a few seconds at best.
Yes, I would believe that claim if they were talking about changing TIRES, certainly the right set of conditions exist to make that claim when changing FRAMES.
Let’s put it another way. Would you believe there is a set of atmospheric conditions that would allow you to save 10 watts using identical equipment from one criteria to another?
I think the change from the Kinesis “carbonaero” fork to the Lotus Sport 110 fork is nearly 100g at low yaw IIRC.
Interesting that Tyler Farrar did not want to have those 9 magical watts in today’s race…
The bike is so good, that he decided not to ride it and spare the competition I suppose, give them a head start I suppose.
Interesting that Tyler Farrar did not want to have those 9 magical watts in today’s race…
The bike is so good, that he decided not to ride it and spare the competition I suppose, give them a head start I suppose.
My suspicion is that there may have been other considerations in regards to the rider’s bike choices today other than what is being speculated…
My recent P3 to P4 upgrade is showing exactly the gains I would expect to see based on Cervelo’s claims. Same componests and position. Only change was the frame.
I expect the same out of my soon to arrive white S5.
As in perhaps the bike rides like piece of wood. Aero is only the end all be all if bicycle racing was a math equation, which it is not.
Of course it is not the end all be all
But when bike weigh differs only by a few grams, and stiffness is sufficient, what is left is aerodynamics and people making up a comfort issue that doesn’t exist
One thing people seem to be missing is that Cervelo is claiming 9 watts at 30 mph in a windtunnel. I’m not one that thinks a wind tunnel test isn’t valid, but there are differences between a number you get in a wind tunnel and what happens in a real race.
Cervelo found 9 watts @ 30 mph in a WT
Cervelo says that equals 7 watts in a group
Using the TDF for example they don’t average 30 mph, more like 24 mph, so there goes a few watts.
They also don’t ride at a steady 24 mph for the entire distance, quite a bit is up mountains and down mountains. Going up the speeds average quite a bit slower than 24, call it 15 mph, there goes more watts.
Going downhill an aerobike should really shine and in some cases it will, but in during quite a bit of downhill any bike will go downhill as fast as the riders skill so a “faster bike” just means more braking.
A good deal of the riding is at a comfortable pace (for them), Not that I wouldn’t take a few watts less output, but when your going well below maximum how much difference does it make if you are at 60% of FTP or 59.5%.
And to be really picky on the TT and TTT (which is admittedly a very small % of the overall distance) they aren’t riding a roadbike.
All this isn’t to say I think an aerobike is useless or no advantage, it is and I’d like to have an S5, particularly the VWD version if Cervelo wants to send me a tester, but taking Cervelos claim (which I suspect is accurate) that the bike when tested in a WT saves 9 watts @ 30 mph with a rider in the aero position, and translating that into “A rider in the Tour will save 9 watts over the course of the race” is a gross exaggeration.
30 is the new 9.
