anyone have any insights, have data showing an aero edge using either a Conti 5000TL vs the Vittoria Speed in 25 mm tires
both measure 27mm on rim but just curious if anyone has seen an advantage for either tire?
keeping Crr out of discussion
cheers
I have no data to support my claim but I would go tubeless. I switched to tubeless on mine and get a smoother ride ( am able to ride 80-85 PSI vs 110 on clinchers), puncture protection with the sealant( my friend and I were riding and went over glass, I heard a woosh for about 1 second and mine sealed while he had a stop and change his tube. I hear a lot of “It’s hard to change” but of the 5-6 punctures I have got since riding, only 1 has been significant enough for me to stop briefly only to add air on the road and the rest I was able to simply keep riding and just add air befoe leaving on my next ride. After nearly 5000 miles on tubeless last year, I swapped out carrying an emergency spare tube and simply carry 1 extra CO2 on my rides now. I recently even switched over my road bike which had a low-mid range set of carbon wheels I wasn’t all that impressed with and was thinking of replacing and converted to TL and they now feel as nice to ride as my Enve 7.8s for 1/3 the price. The cost of converting might some out to buying an extra tire which in the grand scheme of high end bikes is almost nothing and I think it is one of the best upgrades for the buck you can do.
They feel smoother because you were riding wayyyyy too high a pressure on clinchers, and likely still on tubeless for that matter. I ride 25mm gp5000s with latex and run them around 90psi. And I’m on the larger side (170lbs). I think it was enve or Zipp that published tubeless psi recommendations for their wheels and they pretty much fell around 70 psi. There’s also a lot of evidence from very smart people that it’s better to err on the side of less pressure than more.
I know I can ride lower on Clincher, but I generally run 100-110 to stay about midway in between what my tire recommends and to avoid pinch flats.
On Tubeless without the worry of pinch flats, even the upper end of the recommended tire pressure is only about 90 psi, I have confidently ridden as low as 25 psi
They feel smoother because you were riding wayyyyy too high a pressure on clinchers, and likely still on tubeless for that matter. I ride 25mm gp5000s with latex and run them around 90psi. And I’m on the larger side (170lbs)e.
Sounds like your PSI is a little high also considering tire size and your weight.
Yeahhh. I’ve always been scared of going too low but I just put on some new wheels so I’m going to go for a test ride today and try around 85psi. Just listened to the Marginal Gains podcast with Josh yesterday though reaffirming what I already knew so I just need to make the jump to lower.
Go to the bottom of this page and you’ll get pressure recommendations depending on rider weight for all of Enve’s modern wheels. You are riding them way too high.
Do you follow what Enve recommends (57psi for my weight) or what Continental recommends(80-109 psi)? Why is there such a big dependency between the two recommendations?
https://www.continental-tires.com/bicycle/tires/race-tires/grand-prix-5000-tl
I would generally follow what the tire manufacturer recommends, or does Enve also make a tire as well?
https://blog.silca.cc/part-4b-rolling-resistance-and-impedance
Some really good reading there.
ENVE engineer was smoking something when he/she made that tire pressure chart.
Since you are asking about AERO, and not Crr, my guess is the Conti 500 TL will be better. this is based on the vittoria being constructed like a tubular, i.e., the tread is glued onto the casing instead of being vulcanized. This is worse for aerodynamics BUT the Corsa Speed makes up for it when considering combined resistance (Areo drag + Crr losses).
The thing I don’t get about these ultra low psi recommendations is if I look at the Silca charts, I would not come to the conclusion that you want to run 70psi. The minimum crr for most of those charts is 85-100 except for machine roughened concrete, which I assume is not like real world racing conditions.
Yes agreed. what I am trying to parse out. Bike tire rolling resistance site gives the Vittoria Speed about a 1.5-1.6 watt advantage on Crr over the Conti 5000TL
so wondering if there is a significant aero difference to make up for that
SwissSide folks say the tread on shoulder helps with air flow over wheel thus Conti would have advantage the question is how much and if offsets over even exceeds the Crr advantage of the Speed. or better yet does it even make a difference in real world or only in tunnel
…or better yet does it even make a difference in real world or only in tunnel
Contrary to popular opinion, wind tunnels exist within the real world.
Yes have fun racing in one
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I can’t answer your question exactly, but I did wind tunnel test 5000 25 vs 23 on an Enve … and I use 23. The answer to your question may lie in wind conditions … more expected yaw would favor 5000, less the Vittoria, though it will be slower aerodynamically regardless.
Interesting timing on this. I’ve been looking at this as well-- which tire for masters nats TT-- Vittoria Speed or the Conti? I may not be reading the results correctly but AeroCoach has some data in their wheel comparisons. If I am reading this correctly- and I may not be- they show the results of the Enve 7.8 against their Titan on one page and on another page against their Zephyr. The Enve appears to test much better with the Conti. I kept looking at the two charts for a while to try and see why the wheel tested so differently and then I saw their obvious note of the tires used in the testing. Also, if you can find a pic of Kristian Armstrong in either nats or worlds she was riding a Enve 7.8 on her Cervelo. I would very much like to know which tire she rode in Worlds. My understanding is that she is a fanatic on testing. Now I’m going to confuse the issue more, and I would say don’t read too much into this (I’m not.) but when I was in Los Angeles for some testing with Jim Manton last year, he was able to borrow Kristian’s Enve 7.8 for me to test. It had a Conti on it. Okay, I’ve shared all I know and don’t know. I hope you’ll let me know if you learn more.