Err... why do you believe the commercial version features latex tubes?

commercial versions of continentals don't have latex in them.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

If it can help though, I inflated a Conti Podium TT last week and a Conti Competition and today the Competition still has almost full original pressure and Podium TT is almost flat. So maybe the Podium TT uses a thinner butyl tube (like the supersonic) and the Competition a thicker one.

No sure information... just what I found out on the new ones I have.

interesting, where did you get the podium?
maybe it just has a leak? haha

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

can't find anything on Conti's site about latex in the podium tubular, but this shop claims it:

http://www.cyclebasket.com/...L_Podium_TT_Tubular_


Need to know if true! this is important! =)

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I once bought Schwalbe Ultremo tubulars from an online shop where it said they featured latex tubes. They held pressure for weeks (if not months) so it was clearly not correct. I generally wouldn't trust shop information.

At one time Tufo made the Schwalbe tubulars. I tested a Stelvio 25 tubular that a local pro had on their back wheel - 0.000373. I also tested some prototype Schwalbe tubulars a couple of years ago which rolled very well and definitely had latex tubes.

That is interesting. A latex tube will lose ~ 1 psig per hour. I don't have any data on the thin butyl tubes but I'd guess they would be similar to the polyurethane Green Light tubes which hold pressure almost as well as standard thickness butyl. I suppose you could have a slow leak but it's not practical to submerge a racing wheel to find out. A loose valve core is common however.

Typo. Shoot.

doesn't look like there is rolling resistance data?

Wonder if there is any for the ASC Conti line pre-Black Chili?

"Its a butyl Supersonic 0.45mm tube in there" via @contityres

Well for sure that puts it behind a Vittoria EVO Corsa CX but by how much?

something like 1.3 watts per wheel considering the latex alone. Maybe less if they use a thin butyl tube.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

This is for clinchers but probably very true also for tubulars.

Different tubes at same pressure for same tire graph AND different pressures for same tire and tube graph :

http://imageshack.us/...urdifferenttube.jpg/

so yeah, ~1.3 to ~1.5 watts per wheel, even if the butyl is thin

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Probably??

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http://bikeblather.blogspot.com/

For the comparison between Corsa CX and Podium TT, I don't have the direct comparison but here is the closest I have.

Tour Magazin 2010 tire test.

Conti Podium 22 (not sure if it is the exact same version that's being sold in 2012) :

21,6 x 19,4 Millimeter
225 Gramm
33,6 Watt
36,1 Watt
180 Sekunden
28,6 km/h
Schlauchreifen, Butyl


Vittoria Crono Evo 22 320 tpi

20,7 x 18,6 Millimeter
184,7 Gramm
33,2 Watt
34,6 Watt
5 Sekunden
28,6 km/h
Schlauchreifen, Latex


From there I can only make assumptions : Crono is slightly faster than Evo CX, Podium is slightly slower than Crono so Podium is probably close to Evo CX 21 in RR and in Aero and slightly slower in RR but more Aero than Evo CX 23.

Well... sorry I have no scientific evidence of this... but at least I hope the Tour numbers help in the discussion ;-) .

I knew I had another more complete german tubes (latex, light butyl, strong butyl, etc.) test somewhere, found it ;-) :

http://img444.imageshack.us/.../rbm201009tubes1.jpg
http://img685.imageshack.us/.../rbm201009tubes2.jpg

that maxxis flyweight got close!

I need to convert to german. they have better bike magazines.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Hmmm...there should be a bigger spread between the butyl and latex power (more like 15% lower for latex) than what they are showing there...

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http://bikeblather.blogspot.com/

Careful...as much as people complain about the "fragility" of latex tubes, IME lightweight butyl tubes are even worse...they tear just looking at them (they have nearly NO elasticity whatsoever).

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http://bikeblather.blogspot.com/

Ditto, everyone who I know that has had multiple, repeated flats has either been from a foreign object in the tire, bad rimstrip, or lightweight butyl tubes. I live near a performance outlet and people keep buying the things on sale, then having no end of problems.

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Styrrell

I'll triple that, lightweight butyl tubes are damn scary. I've had two. One just blew apart at 80 psi when pumping up a tire. Another, tore near the valve stem. That was enough. Conversely, latex tubes seem nigh bullet proof.

From twitter exchange:

@ContiTyres Does the new Podium TT tub have a latex or butyl tube?
@NickEnglish21 Its a butyl Supersonic 0.45mm tube in there

ContiTyres is the UK distributor for Conti.

I have an older Podium Time Trial tub, the 'Lightweight by CarbonSports' version, looks the same as the Podium TT, but who knows. It doesn't lose pressure as fast as my Veloflex Record or latex tubed clinchers.

Duncan