cannondale aero road bike
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You don't need an "Aero" bike. Although, Cannondale claimed due to the narrow tubes of the EVO it was pretty aero already all things considered.
I believe Sagan won a ton of races on the EVO...so, EVO will/can perform and win at the World Tour Level, but only with the right person on it. True with all bikes for the most part that are "higher-end" in our World of enthusiasm/amateur competition etc.
I believe Sagan won a ton of races on the EVO...so, EVO will/can perform and win at the World Tour Level, but only with the right person on it. True with all bikes for the most part that are "higher-end" in our World of enthusiasm/amateur competition etc.
Krackor wrote:Skylark wrote:One thing which ought to have been learnt is that we shouldn't second guess any experiment until we have the data.
We do have some data though.
http://www.bicyclerollingresistance.com ... ke-reviews
This doesn't directly measure the power savings of good frame suspension, but it gives us an idea of the magnitude of suspension-related losses involved. If bump absorption were a large factor, one would expect that lowering tire pressure will reduce rolling resistance, since that improves compliance over bumps. Of course you're competing against the internal losses in the tire as the pressure drops, so lowering pressure too far will become worse at some point. This is why people don't run 50 psi in their road tires, nor do they run 200 psi.
What we do know is that lowering tire pressure from 120 psi to 100 psi does not improve rolling resistance in any of the tested cases above. The best example is the GP4000SII w/ latex tube, that only loses 0.5W going from 120 to 100 psi. If there's any gain to be had from improving the bike's ability to track the ground I would expect it's not above the magnitude of 1-2 W, otherwise I would expect to see some of these tires losing rolling resistance as they lost pressure.
You're right that a real test is the more definitive way to tell whether frame compliance improves straight line speed on an average road, but smell test tells me that it won't amount to the magnitude of aerodynamic gains of a properly designed aero road frame (10-20W).
Yes indeed tyre pressure has a sweet spot for rolling resistance and thereby W saved. The solution is widely recognized.
You wonder why then the Evo is asking to maintain the tyre pressures at traditionally conservative levels. I digress. If I am not mistaken the Speed Save stays also flex sideways rather than just vertically. This certainly is my perception when gunning it on the flats around corners.
It's a little more complicated than that I fear. I'm inclined to think that the stays are doing more than can be modeled with lower tyre pressures alone. Couple that with the slender profile of the tubes and the aero question in this bike becomes nontrivial.
Tinea Pedis wrote:Only they used CFD and Kamm tail design to re-shape every tube on the new Evo. So...Skylark wrote:In addition, they haven't improved the overall geometry either until now.
Why fix something that ain't broke? The Cannondale geo is recognised as one of the most balanced going.
And their Pro team was totally shit last year, but have started super well in 2016. So that's 3 strikes - on top of what others have pointed out to you 'Liggero' (or whatever your original multi actually was).
I met David Devine last year and asked if an aero bike was coming for 2016, said "no". And not because it doesn't interest them, but no for now at least. Could be a red herring, wouldn't be the first time a company has used it. I'll see what else other mates might know.
As for the Slice, the road version is still fast enough and their new Tri one isn't bad. And that's where they want to pick up sales.
Please show me explicitly which tubes precisely on the Evo Mark I exhibit a Kamm tail design?
My answer is none and certainly doesn't warrant any CFD calculation therein. Certainly they reduced the diameter of the tubes (DT, Seatstays) and any elementary CFD calculation of a flow around a circular obstacle proves the lower extent of turbulent flow behind the obstacle based on the obstacle's diameter. This is almost an axiom in CFD without requiring to do any further research or additional calculations. I believe Trek have done more work than Dale on CFD analysis given the peculiar shape of the TT in the Emonda for example.
I digress.
By geometry, balance is certainly one aspect of it. Though not all of it. I've specifically been referring to the height of the bike from the ground. Lower is better and this is an area for improvement. Although I believe they have now lowered the BB in the Evo Mark II by 3mm.
I digress.
Please stop unfounded accusation of ID solicitation with other individuals on the board. If you have a question please ask me directly.
I digress.
Last edited by Skylark on Tue Mar 08, 2016 11:18 pm, edited 1 time in total.
Zigmeister wrote:You don't need an "Aero" bike. Although, Cannondale claimed due to the narrow tubes of the EVO it was pretty aero already all things considered.
I believe Sagan won a ton of races on the EVO...so, EVO will/can perform and win at the World Tour Level, but only with the right person on it. True with all bikes for the most part that are "higher-end" in our World of enthusiasm/amateur competition etc.
You don't need a lightweight or "weightweenie" bike either. At least if you race competitively, a true aero frame will give you more performance benefit than saving a few hundred grams off your bike.
While Cannondale might have improved the aero aspect of the Evo compared to it previously, I doubt it matches the level of the Cervelo R series in terms of aero and much less anywhere close to the Cervelo S5/Felt AR/Trek Madone/Specialized Venge/Canyon Aeroad of this world.
Yes, the legs, lungs and heart power the bike. However, like for like, you will be faster on an aero frame than on a frame that might save you a few hundred grams. If that doesn't concern someone to be faster and more efficient, so be it.
"Marginal gains are the only gains when all that's left to gain is in the margins."
That's pretty bad ass too, but I prefer the Cannondale aesthetically. Might make a good for fun project if I could ever do something like that justice in a race.
Wasn't there a guy on here who uses TT frames because of their geo for road riding?
Sent from my iPhone using Tapatalk
Wasn't there a guy on here who uses TT frames because of their geo for road riding?
Sent from my iPhone using Tapatalk
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