Tire Rolling Resistance Study
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I find Gators a bit slippy and I think they ruin the ride, but each to their own.
Specialized's compound is the grippiest I have used whilst still remaining fast according to the tests I have seen. However it cuts more frequently than Conti as far as I can see (n=1 tyre). I did see some SWorks tubulars in a Specialised Concept store but I think they were £90 a throw....
Specialized's compound is the grippiest I have used whilst still remaining fast according to the tests I have seen. However it cuts more frequently than Conti as far as I can see (n=1 tyre). I did see some SWorks tubulars in a Specialised Concept store but I think they were £90 a throw....
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BrianAllan wrote:Tinea Pedis wrote:BrianAllan wrote: Firmly placing it in the realm of racing. Most people that care about 3 watts are racing on tubulars.
Sorry Brian but you keep trotting out this stat and it's simply untrue for the majority below WT level. Australia. Asia. Belgium. Raced in them all and clinchers are the majority. Not as much in Belg but certainly in the first two.
And like David said, when it comes to TTs clinchers are fast taking over. WT level and below.
They (Velonews) hit the growth market, simple as that.
I'll concede that I can't attest what the global market uses in elite racing. But but in United States the vast, vast majority of the elite (pro 1/2) are using tubulars. If you'd like to dispute this, then supply some evidence. 8 or so years of racing and I can't think of a single person using clinchers unless they had flatted their tubies. A few people randomly using clinchers here and there is not a significant market segment. Therefore if you're trying to supply a relevant performance comparison (keyword: relevant) you need to supply reference comparison between a few tubular offerings.
I don't dislike clinchers. If they're faster than tubulars, then I think it makes a lot of sense to use them in TT's, where the incurred weight penalty isn't as a significant. However, considering this test doesn't support a performance argument over tubulars, I'm not sure while people are so up in arms. If you like your carbon clinchers, good for you. They're just not really used in elite racing.
Sorry, but UHC raced on clinchers for years until Maxxis finally made a tubular. Kenda did as well. Mike's Bikes (number 1 ranked amateur elite team in the U.S.) races on clinchers (S-Works turbo cotton). Herbalife 24 (2nd highest rated) also did last year.
Again, pro teams often use tubulars for tradition, safety, and then weight reasons. When you have a care full of wheels its not that big of a deal and they're ever so slightly lighter. Until the past few years only a few clincher tires were as fast or faster than tubulars, but now many more seem to be.
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BrianAllan wrote:Fine. They could have used tape to have a consistent glue thickness across multiple wheelsets.
You do realise that tape would make it appear that even Crono CS track tubs roll like training clinchers?
If you want to use tubs, just get Corsas and hope they never change the construction. None of the people who care about CRR testing are particularly interested in the time investment it takes to test tubs.
The battle lines are now drawn between standard clinchers and tubeless, so expect to see a lot more testing investigating that comparison. Probably ignoring tubs, just like this test.
For testing tubs with glue, ideally you'd do a run(s) for each tyre with the same wheelset with as close as possible to the same glueing job as you could manage. Sounds like a really fun weekend!
That said at least tape will provide a consistent relative measurement of tubular performance, and if you roughly know the crr delta with glueing you could interpolate and annoy the purists
One point that gets lost in this discussion is that latex tubes are safer (IMO much safer) in a tubular tyre, to the extent that I regard butyl in clincher vs latex in tubular as nearer apples with apples ...
That said at least tape will provide a consistent relative measurement of tubular performance, and if you roughly know the crr delta with glueing you could interpolate and annoy the purists
One point that gets lost in this discussion is that latex tubes are safer (IMO much safer) in a tubular tyre, to the extent that I regard butyl in clincher vs latex in tubular as nearer apples with apples ...
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Stiff, Light, Aero - Pick Three!!
Stiff, Light, Aero - Pick Three!!
I wonder since when the superiority of clinchers versus tubulars CRR is so well established...
There is one study which shows the opposite is in fact true: http://www.biketechreview.com/tires_old/images/AFM_tire_testing_rev9.pdf
Granted, it's 5 years old, and no current top-performers are there, but notice that the same tyre (Veloflex record for example) was faster in tubular version (when properly glued) compared to clincher version (which was of course tested with latex tube) - same thread compound, thickness, casing...
Then there is this piece of information shared by Paul Lew, which concludes that for optimal aero performance, it's necessary for the tyre to be much narrower then brake track of the rim:
http://aerogeeks.com/2014/04/03/aeromail-tire-size/
If only aerodynamics is considered, it would be ideal to have 14mm diameter tyre on 25mm wide rim ! Of course that's really extreme and the penality in CRR would probably offset the aero gains, but still, when only concerned with lowest combined CRR/Aero drag, especially for front wheel you need to fit tyre which is considerably narrower then rim, maybe 20-21mm tyre for 25-26mm rim would be optimal. And this is of course much easier and safer to do with tubular tyre, as you can't safely mount 21mm clincher to 19-17c ETRTO rim.
So no, just saying "Tony Martin rides them" is not enough for me as a proof that clinchers are inherently faster. Please provide some compelling evidence, comparative CRR/Drag studies (No, not that BikeRadar "study"), i would be more then willing to take that into account and maybe change my mind.
There is one study which shows the opposite is in fact true: http://www.biketechreview.com/tires_old/images/AFM_tire_testing_rev9.pdf
Granted, it's 5 years old, and no current top-performers are there, but notice that the same tyre (Veloflex record for example) was faster in tubular version (when properly glued) compared to clincher version (which was of course tested with latex tube) - same thread compound, thickness, casing...
Then there is this piece of information shared by Paul Lew, which concludes that for optimal aero performance, it's necessary for the tyre to be much narrower then brake track of the rim:
http://aerogeeks.com/2014/04/03/aeromail-tire-size/
If only aerodynamics is considered, it would be ideal to have 14mm diameter tyre on 25mm wide rim ! Of course that's really extreme and the penality in CRR would probably offset the aero gains, but still, when only concerned with lowest combined CRR/Aero drag, especially for front wheel you need to fit tyre which is considerably narrower then rim, maybe 20-21mm tyre for 25-26mm rim would be optimal. And this is of course much easier and safer to do with tubular tyre, as you can't safely mount 21mm clincher to 19-17c ETRTO rim.
So no, just saying "Tony Martin rides them" is not enough for me as a proof that clinchers are inherently faster. Please provide some compelling evidence, comparative CRR/Drag studies (No, not that BikeRadar "study"), i would be more then willing to take that into account and maybe change my mind.
bsavery wrote:Couple thoughts. When do we start claiming velonews was paid off by specialized???
hahaha my first thought as well.
As long as there are choices, these tests will exist.
For me as a recreational rider, the groupings are close enough to not matter. what guides my choice is feel and durability. Its an interesting read now that winter is here.
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KWalker wrote:BrianAllan wrote:Tinea Pedis wrote:BrianAllan wrote: Firmly placing it in the realm of racing. Most people that care about 3 watts are racing on tubulars.
Sorry Brian but you keep trotting out this stat and it's simply untrue for the majority below WT level. Australia. Asia. Belgium. Raced in them all and clinchers are the majority. Not as much in Belg but certainly in the first two.
And like David said, when it comes to TTs clinchers are fast taking over. WT level and below.
They (Velonews) hit the growth market, simple as that.
I'll concede that I can't attest what the global market uses in elite racing. But but in United States the vast, vast majority of the elite (pro 1/2) are using tubulars. If you'd like to dispute this, then supply some evidence. 8 or so years of racing and I can't think of a single person using clinchers unless they had flatted their tubies. A few people randomly using clinchers here and there is not a significant market segment. Therefore if you're trying to supply a relevant performance comparison (keyword: relevant) you need to supply reference comparison between a few tubular offerings.
I don't dislike clinchers. If they're faster than tubulars, then I think it makes a lot of sense to use them in TT's, where the incurred weight penalty isn't as a significant. However, considering this test doesn't support a performance argument over tubulars, I'm not sure while people are so up in arms. If you like your carbon clinchers, good for you. They're just not really used in elite racing.
Sorry, but UHC raced on clinchers for years until Maxxis finally made a tubular. Kenda did as well. Mike's Bikes (number 1 ranked amateur elite team in the U.S.) races on clinchers (S-Works turbo cotton). Herbalife 24 (2nd highest rated) also did last year.
Again, pro teams often use tubulars for tradition, safety, and then weight reasons. When you have a care full of wheels its not that big of a deal and they're ever so slightly lighter. Until the past few years only a few clincher tires were as fast or faster than tubulars, but now many more seem to be.
Your argument seems to be that clinchers are capable of winning races. Did anyone state the contrary? I would argue the reason Maxxis teams rode clinchers was not out of preference, but due to sponsorship obligations. If anything, that goes against your argument. I also recall UHC using rebadged tubulars with Maxxis logos before they made them. That’s awkward.
I dispute that they’re ‘ever so slightly lighter’. When you’re racing a race with climbing, you care about 200g in your wheels.
Last year both Kenda and UHC raced tubulars. I just pulled photos from the Tour of the Gila, and it’s pretty clear they’re on tubies.
- Tinea Pedis
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Does anyone have a link to the raw dataset? I'd like to do a re-analysis in my spare time since I find the presentation and formatting of the results a bit poor.
It's in french but there you have some serious test and datas for those who doubt ...
http://cyclesetforme.blogspot.be
I love the feel of goods tubulars ( veloflex roubaix , vittoria corsa with cotton gum walls ) so it piss me to recognize it
He tested a pair of wheels lighter with tubular veloflex chrono or the less robust one I don't remember the name and a light clincher on the front :
and a 300 gr heavier clincher wheels with latex tubs and gp400S2 tyres
At constant speed or with series of acceleration measured with a SRM , no différences between the lighter and heavier wheels in an ascent of some km with 7% of grade. The tyre system is responsible for efficiency not the rim
And if the system wheel-tyre is good a constant speed it is also with accelerations
apologize for my poor english
http://cyclesetforme.blogspot.be
I love the feel of goods tubulars ( veloflex roubaix , vittoria corsa with cotton gum walls ) so it piss me to recognize it
He tested a pair of wheels lighter with tubular veloflex chrono or the less robust one I don't remember the name and a light clincher on the front :
and a 300 gr heavier clincher wheels with latex tubs and gp400S2 tyres
At constant speed or with series of acceleration measured with a SRM , no différences between the lighter and heavier wheels in an ascent of some km with 7% of grade. The tyre system is responsible for efficiency not the rim
And if the system wheel-tyre is good a constant speed it is also with accelerations
apologize for my poor english
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mattr wrote:I wish people would stop calling that a "test".
What is it then?
And great link and translation romalor merci.
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