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Discussion Starter · #1 ·
Just curious really why my 25mm Vittoria Open Corsa CX iii tyres would have the following information on the sidewall. "Tubular pressure: 8-14Bar/115-200 PSI mounted on tubular specific rim". Given they are a clincher tyre I fail to see the relevance of a reference to a tubular one. A manufacturing mistake, some kind of homage to its tubular history, something else?? Seems strange.

These are the first set of Vittorias i have owned so have nothing to compare.

see photo....
 

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A wheelist
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Maybe, and this is just a guess, they use the same tread mold for clincher as they use for the tubular version.

I found this on the Art's Cyclery site -

"The Vittoria Open Corsa CX III has taken over as Vittoria's top model clincher and shares all the technology of the popular tubular version, including: 320 tpi for incredible road feel, a ridiculous 200 psi max pressure (in a clincher!).............."

I would question the ability of any clincher rim's bead hooks to withstand such pressures. Those kinds of pressures are reserved for smooth indoor wooden velodromes - and if anyone needed anything close to 200psi they would certainly be riding on tubulars. I never used more than 130psi on such a velodrome with clinchers (Conti Supersonics on Open Pro rims).
 

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Discussion Starter · #3 ·
I thought something similar with respect to using the same tread mold but it still seems quite odd from a high end tyre maker on what is essentially one of their flagship products.
 

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I ride a 23mm Corsa and run 85psi in the front and 90psi in the rear (I'm 170lbs, no pinch flats yet). I'm not sure why you would run more in a 25mm tire unless maybe you were racing but even then 120psi is more than enough.
 

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'brifter' is f'ing stupid
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I ride a 23mm Corsa and run 85psi in the front and 90psi in the rear (I'm 170lbs, no pinch flats yet). I'm not sure why you would run more in a 25mm tire unless maybe you were racing but even then 120psi is more than enough.
If 90psi has better traction, is more comfortable, AND has less rolling resistance explain why you'd use higher pressure if 'racing'.
 

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If 90psi has better traction, is more comfortable, AND has less rolling resistance explain why you'd use higher pressure if 'racing'.
Actually higher pressure (120psi) has better rolling resistance so for racing I might understand (going from 80 to 120psi is 1w in rolling resistance).

Vittoria Open Corsa CX III Latex Tube Rolling Resistance Review



I wouldn't personally though, I like my 85-90psi with more comfort and better traction.
 

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Discussion Starter · #9 ·
You guys have missed the point of my post. I don't want to run 200, im perfectly happy with 80/90.
My question was why on a clincher tyre do they talk about tubular pressures on a "tubular specific rim" which is impossible with that tyre.
 

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'brifter' is f'ing stupid
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You guys have missed the point of my post. I don't want to run 200, im perfectly happy with 80/90.
My question was why on a clincher tyre do they talk about tubular pressures on a "tubular specific rim" which is impossible with that tyre.
They put the wrong hot patch on that tire/batch?
 

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Perhaps.

If anyone else with an Open Corsa CX wants to have a look at their sidewall and let me know what it says? It's just curiosity more than anything.
There are literally hundreds of photos on the interwebs that look just like this:

Bicycle tire Tire Bicycle wheel rim Automotive tire Bicycle part

The hot patch on the tubular looks like this:

Bicycle tire Bicycle wheel rim Automotive tire Bicycle part Rim

You obviously have an 'open' tire. Just inflate it to the pressure you like and believe that production mistakes happen. You don't have some secret prototype high pressure clincher.
 

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A wheelist
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If anyone else with an Open Corsa CX wants to have a look at their sidewall and let me know what it says? It's just curiosity more than anything.
I went and checked my stash - they all have TWO sets of pressures - one set on one side of the tread and the other set on the opposite side. They say -

Clincher Pressure: 8-10bar, 115-145psi.
Tubular Pressure: 8-14bar, 115-200psi.

Then the red label says "Press. 7-9bar (100-130psi)

How 'bout that eh? So I was right - they use the same mold for clincher and tubular. But the label somewhat contradicts the molded in figures. :eek:

I've never seen any of that before (especially the molded-in pressures) and I don't give a rat's arse as I always use 80f/90r.
 

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Vittoria calls them an open tubular aka clincher and no doubt both tire types use the same mold.
 

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Discussion Starter · #17 ·
@Mike T
Hmmm, i didn't even think to look at the other side of the tyre but yeah, the clincher details are there.
Incidentally, my red label says 115-145
 

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Discussion Starter · #20 ·
I noticed there is a tiny arrow on the edge of tread. I assume that means rotating direction, not that it matters much.
Yes, I assume so, Although the edge tread is slanted in a particular direction, not sure how much real world difference there would be. Unlike the Conti's which are labelled both sides, at least with these if you keep the red labels drive side, you get the direction correct.
 
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