Sunday, March 19, 2017

Holy Moly...Vittoria Corsa Speed TLR




Since their introduction, there's been a lot of "buzz" about the newest Vittoria tires which incorporate Graphene into their tread compounds. In particular, the Corsa Speed model has been touted in various locations as the fastest tire. Despite being only offered in one size (23C), it's intriguing in that it's the first "Tubeless Ready" tire on the market that utilizes the "open tubular" type of construction, with a flexible cotton-casing and a separately glued-on tread. I finally acquired a set of the Corsa Speed tires and put them to the rollers. So...are the fast? The answer to that is an emphatic "YES!"

To cut to the chase...I tested the Corsa Speed in 3 ways:

  1. First, on my standard test wheel (Mavic Open Pro) with a latex tube inside, 120psi.
  2. Next, on a Jet6+ wheel with a latex tube, 100psi
  3. Lastly, on the Jet6+ wheel set up tubeless, with 40ml of Orange Seal.
As I've described in the past, I've found that the 120psi results on the Open Pro rim match the 100psi results on the Jet6+ rim, and this way I could confirm that once again while having a result (on the Open Pro) that can be more directly compared to the majority of tire test conditions in my spreadsheet. Here's the results:

Vittoria Corsa Speed TLR 23C, latex tube, Open Pro (120 psi)  = .0025, 23W for pair @ 40 kph
Vittoria Corsa Speed TLR 23C, latex tube, Hed Jet6+ (100 psi) = .0025, 24W for pair @ 40 kph
Vittoria Corsa Speed TLR 23C, tubeless, Hed Jet6+ (100 psi)    = .0025, 24W for pair @ 40 kph



As you can see, the results are basically identical, with rounding differences in the 5th decimal place of the Crr estimate accounting for the 23W vs. 24W values in the estimated power for a pair of tires.

The Corsa Speeds are the new champs on my list...and not by a small amount, but by a fairly significant jump! The next closest new tires are a full 3W behind for a pair at 40kph.


As I described above, the Corsa Speeds are built in a traditional Vittoria Corsa manner, with a cotton-based casing and a separate tread. One of the things that's different about this particular tire is that there is a grey, flexible coating (feels to be a latex-based coating to the hand) not only on the sidewalls of the tire, but also on the majority of the inner surface as well. This most likely is done to help enhance the air sealing capabilities of the tire...and it seems that this particular construction for tubeless road tires might require more sealant being used on initial installation. I found that the air loss for the tire was unacceptable until I had inserted ~50-60ml of sealant. After that, the tire has held air perfectly fine.

Coating inside casing. Appears to be same as sidewall coating


This is a thin tire, and I'm not sure if it has any type of puncture breaker under the tread...and so most would be concerned about it's durability. To test that out, I've been running it as a rear tire on my road bike and have currently ~500 miles in "not so pristine" road conditions. We've had a good amount of rain this winter in Southern California, and the road shoulders are littered with debris right now. So far the only mishap has been a small staple that was picked up by the tire. I noticed the staple prior to a ride, and hadn't spun the tire before pulling it out. That was a mistake in that it took me a bit to get the sealant to work on the very small hole...but, eventually it held and the sealant has formed a nice plug in that area that is holding just fine.


So far so good...I'm really liking this tire. I've also recently discovered a tubeless repair technique that I think will dramatically alter the "hassle factor" of dealing with a hole large enough for sealant to have a hard time plugging. I'll be going over that technique in a future blog post.


There you go...a new "top dog" has been confirmed.

30 comments:

  1. I am less concerned about the durability and more interested in your experience mounting this tire on the various rims. Also curious about the measured with of the tire after being inflated.

    Thanks for testing!

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  2. It was no more difficult to mount on the old Open Pro than any other tire, despite the thick cotton rim tape I have on there. It also wasn't overly difficult on the Jet6+ rim, which with its tubeless-ready rim isn't the easiest to mount tires on at times. Measured widths are in the spreadsheet: 23.7mm on the Open Pro at 120psi and 26.9mm on the 21mm internal width Jet6+ at 100psi.

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  3. Would you say these tires are faster than the Continental Supersonic? Im looking for a race day tire that will do well on a smooth road up a mountain climb, and will fit properly on my Dura Ace C24 clincher wheels...

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    1. Their Crr is significantly lower...unknown is the aerodynamics on a particular wheel as compared to an SS, and if any differences there overcome the Crr differences. But, if you're talking about a mt. climb, then the aero is going to be a lower factor...so, go with the lower Crr :-)

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    2. The other thing to take into account is the weight, with the Supersonics coming in at a staggering 150g per tire, a full 75g lighter per tire vs. the Corsa Speed. Do you think the lower Crr of the Corsa Speed outweighs the weight benefits of the SS (pun intended)? Now you've got me leaning towards getting the Corsa Speed. It also seems like it likely offers much better puncture protection and wear vs. the SS. But dont forget, the tires will be used on primarily on long mountain climbs, so weight is a factor...

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    3. If you do the math (I have) you'll quickly see that tire mass is not even a performance parameter even worth considering. That's mostly why I don't even bother weighing the tires I test. It's not going to be a determining factor in any tire choice I make.

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  4. How hard are these tires to mount onto the Jet+ rim on a scale of 1-10 with a 23mm GP4000S II being a 5 and an IRC roadlite tubeless being a 9?

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    1. Somewhere between the 2...when putting it on tubeless, I've found it's best to end at the valve, since it's not possible to push the seated valve up into the tire to create room like you can with a tube.

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  6. You are correct, this tire rips! I did find them a bear to install with a latex tube on my Bullet Ultras however. A narrow butyl tube was much easier. But...once on I loved them.

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  7. Any issues with the rim of the HED as a tubeless. I believe it is not a true tubeless setup and some riders have had problems with air leaking at the joint.

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    1. I've had no problem. Although the Jet+ isn't touted as being tubeless-ready, as I understand it, the rim extrusion is basically the same as the Belgium/Ardennes rim, which is. It has the same rim bed features, with the dropped center channel and the raised bed portions under the bead to act as a "lock". The main difference is mostt likely the carbon cap on the Jets, on which you most likely don't want to just tighten down a tubeless valve nut onto by itself. I'm using the excellent Silca tubeless valves, which come with an aero-shaped rubber spacer to spread the load out better from the nut...plus, I try to be gentle with tightening that ;-) Otherwise, 2 layers of Stan's or Silca rim tape and Orange Seal seems to work quite well for me.

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  8. Tom for TT's I normally run a supersonic 20c on the front of my 808 Firecrest and Supersonic 23 on rear of my Super9 disk. Would you switch to the Corsa speed for both tires or just the rear? Thanks!

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    1. I'm not sure...the biggest hesitancy being around the unknown aerodynamic performance of the CS on the 808 Firecrest. I would probably stick with the SS 20 on the front and switch to the CS on the rear.

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    2. Awesome. Thanks Tom I'll wait until there's some aero data on the tire before considering switching the front to the Vitorria. As always huge thanks for everything you do for the TT community!

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  9. Hi Tom. Thanks for this. 2 things,

    1/ A typo
    "So...are the fast?"

    2/ I grabbed one of these for racing but wasn't sure about their puncture resistance. Anyway, I had it mounted on a Flo 60 front wheel and got it all sorted to hold air with 50ml of Stans No Tubes Race sealant. I did find it leaked air a little, maybe 20psi over 3-4 days. Better than a latex tube.
    So I took it for a spin on a training ride last Saturday, the day before an up hill TT. I thought I might use these on more training rides too if they don't puncture that easily like you have indicated. (Now, I am not at all blaming you, just wanting to put my experience out there). This was the result:

    https://goo.gl/photos/KNKSG18GufUqMGuS9
    https://goo.gl/photos/rukkPrFYCmSrAZ9y9
    https://www.youtube.com/watch?v=6LciMbrdkzk

    I've never had a tyre lose air so fast; faster than the sealant could block the hole.
    Be careful out there using this tyre. Hopefully my experience was a 1 off, but 1 ride and this result has made me gun shy about buying one of these again.

    Thanks for the site Tom.

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    1. Wow David, sorry to hear about your crash. It's tough to see from the picture of the tire, but is there a slash in the entire sidewall? In the video there sounds like a fairly loud "pop" when it punctured. Do you know what you might have run over to cause that? So far I've only run one of these on the rear. I've had a puncture, but nothing near as large as what you seem to have suffered.

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  10. Thanks Tom. New to cycling (4 yrs) and my first crash. I have had punctures at speed before and I have kept my line and brought the bike to a halt. Not this time.

    Is this photo more clear?

    https://goo.gl/photos/ZuoZczVBSw39HTaKA

    I just measured it and it's about 7-8 mm long.

    If you slow the video down you can see what I run over. It looks metal. I am going to drive to the crash site in the morning to see if I can see it (and collect my water bottle that was left there).

    Do you think I was just unlucky and it didn't matter the tyre, or the slightly thinner Corsa Speed made this worse?

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    1. Hi David...yeah, I'd have to say you were just unlucky. That sort of slice would pretty much take out any tire, and that matches the sound of the puncture (loud pop). I had something similar happen to me with a Turbo Cotton and latex tube setup last year, where I hit the side edge of a pot hole which instantly tore through the sidewall of the tire and the tube. Luckily for me, it was on the rear and I was able to more easily control it.

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    2. Tom,

      I had the exact same cut David had last year.
      Rode the tires a couple of times (tubeless on Boyd 44 carbon clincher TLR wheels) in April before 70.3 Aix en Provence which was may 1st. No problem there. Two weeks later used the wheels again for a Granfondo, had the same cut on the sidewall of my front wheel doing some sprint work (so bike leaning left/right and touched probably a small gravel at same time) and pressure went down very very fast too. 40ml of Orange seal couldn't seal that cut, tried to repair but the tight beads made it a pain in the *** even though I've worked with tubeless on MTB for 15 years now so quite used to tight beads, tubeless rim shapes and so on.
      This kind of situation is where I think road tubeless fails VS clincher with tube or MTB tubeless. This kind of cut often damage your tire (it would damage a Conti SS or whatever) but most often it does not even puncture your tube --> most of the time it makes your tire bulge ever so slightly in the area but you only find out after the ride. There is enough pressure in road tubeless that this kind of cut gets wide open right away and the sealant can't do anything about it. I guess Schwalbe Pro One with "Microskin" is a bit better in that regard but Corsa Speed is a bit scary to me.
      Ended up back to riding Continental with latex tubes at Ironman Nice, Vichy and Barcelone last year (also during all my training) with not a single other puncture.
      So maybe bad luck... or maybe road tubeless with the higher pressure is still a work in progress for the manufacturer in order to offer super fast tires like Corsa Speed that also offer more protection and safety than actual Corsa Speed.
      Just my 2c.

      Pierre

      Ps : yet I loved riding Corsa Speed in tubeless, awesome ride !

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    3. Hi Tom,
      I realised I replied to the article instead of your reply in my last post. Let's blame the concussion.

      So you think if I was running Gatorskins, the same result would have ensued?

      Pierre,

      Interesting you had a similar experience. I am wondering if this is an issue with the Corsa Speed. My other tubeless are all Schwalbe Pro One's so I think I will be sticking with them. Is this Vittoria's first road tubeless attempt?


      I can't see how an inner tube would make a difference here. Tubes, especially under pressure, would be so sensitive to any sharp object that it would be a VERY rare situation that a rip 7-8mm long right through the tyre would not touch or affect the inner tube. But I am no expert.

      I am glad your puncture on the Corsa Speed wasn't as spectacular as mine.

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    4. PS I went back to the crash site to get my bottle and look around the spot you hear the pop and found this:

      https://goo.gl/photos/tE8q34DkZJ4JhhhY9

      It matches the shape of what, in the video, I run over when it punctures.

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    5. Yes, even a Gatorskin would have a tough time fending off something like that...and you definitely wouldn't want to race on those.

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  11. Great blog with the science to back it up! Looking forward to the aero reviews on the Corsa as well as some data on the Michelin Pro Competition (and their respective comparisons to Turbo Cottons from Specialized. Cheers and thanks!

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  12. So the tubeless set up was equal to the latex set up, I was under the impression tubeless would have a lower Crr?

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    1. Hi Jeff, yes...the idea of tubeless tires having lower Crr due to the elimination of the tube is typically in reference to a butyl inner tube. This just points out how little hysteresis losses there are in latex tubes.

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  13. Hi Tom, again great testing and knowledge. I am doing IM Hawaii this year for the first time and trying to gain watts everywhere possible. But I am a bit unsure of Corsa Speed and risk of puncture on the road, where I would have to change the tube (if not going tubeless). What is your thoughts on that? thanx.

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    1. I didn't find them to be overly difficult to manage on either my old Open Pro rim or the Hed Jet+ rims. Others seem to have had differing results though...so, it probably would be a good idea to practice with your setup. That said, I think for that event I would run them tubeless (if you wheels allow) and have as my "first line of defense" one of the Genuine Innovations tire plug kits. That should eliminate the need to deal with the beads except for only the largest of punctures/cuts.

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  14. 100 psi is too high for a tubeless setup on the Jet+ rims, unless you're well over 200 lbs. Try running them at ~80 psi, re-test and see what sort of results you get.

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    1. Hi Scott. Thanks for pointing that out, and please understand that this is fully appreciated. I didn't go into it in this blog post, but the selection of 100psi on the Jet+ rim was so that the results could be directly comparable to ALL of the other tires that had been tested at 120psi on the narrow Open Pro rim. You have to realize that this testing on a perfectly smooth drum is really just a "ranking" of the tire hysteresis losses, and so the comments about what pressures one would run on a "real road" don't directly apply. If you look at my original post on roller testing, you'll get a better feel for what I'm trying to explain: http://bikeblather.blogspot.com/2013/02/tire-crr-testing-on-rollers-chartand.html

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