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"The difference in rolling resistance of the tyres at the top are all to be taken with a large heaping of salt."
Hey, you provided it as evidence. It just happened the evidence proved my point.
"137.5g"
"At least 150g difference"
Well it's not then is it? I already agreed that tubs were lighter. Remind me, how much of a factor this weight is in bike speed... ?"Many races have been won with people riding the last km on flat."
Pics or it didn't happen."Imperial riders are faster, right?"
Clincher riders are faster, imperial or otherwise."Why. You mean there are no punctures or other kinds of tyre defects in races? Heck even on the track I've seen tyres fail-- even explode."
I don't know what point you're making.
You said because wheel swaps were allowed in races, tubs were somehow faster. My point is, if you can swap a wheel when it fails, it's irrelevant what type of tyre is being used."With tubulars they are not 100%"
Correct.
"The tyre (Continental) was completely trashed"
You should've listened to my earlier advice that Continentals are shit. I would've made a tyre boot and ridden home. I've seen people will clinchers with grass to get home.
Actually, with the money I've saved not buying stupid tubulars I'd have just called a cab.
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hippy
To the Firecrests.. Fine that TriTrig thinks they are better but Zipp who make them don't. Let me see if I can find their drag numbers...
The difference in rolling resistance of the tyres at the top are all to be taken with a large heaping of salt. Yes, the rolling resistance of clinchers has vastly improved over the years but your claim was that their rolling resistance is lower.. Note also that, if I recall correctly, Tom uses two coats of Continental cement to glue the tyres. While Conti mastic is quite good it is not the glue with the lowest rolling resistance. It is, afterall, still a softer sticky glue rather than hard. In the Peleton most of the team mechanics don't use it alone but tend to mix other cements in. Don't know what is popular these days but a few years ago Patex was pretty popular with carbon wheels.. On the track-- and I've mentioned this on a number of occasions-- Terokal 2444 is the go-to glue.
Really? Lets look at the Zipp numbers:
CC: 1885g (see http://zipp.com/wheels/808-firecrest---carbon-clincher/# )
Tubular: 1700g
(these are the numbers that Zipp publish on their Web)
Difference: 185g. The font wheel difference is 85g. The rear difference is listed as 100g. That is an average 92.5g per wheel difference.
Lets now look at the difference in weight for the tyres. For the sake of things I'll leave off the weight of the rim tape as its quite similar to the weight of mastic.
My Continental 22 Comps are ~260g, Veloflex Carbons were ~250g, Vittoria Corsas were ~260g,.. again I'm just choosing really robust and not ultralight tyres... Lets go with 260g.
Lets look at tyres that claim to be "similar"... My GP4000SII 23mm were ~210g. My 23mm Open Corsa CX were 220g. Veloflex Master was just under 200g. Lets go with 205g. The lighest inner-tubes around are the Continental Supersonic at 50g but they are scary thin.. Good inner-tubes are generally at least 100g each. Just weighed some of my inner-tubes. My latex Paribas came in at 104g. Vittoria UltraLight (Butyl) was 111g. Both weighed on an analytical balance. Lets say 100g. Sum tyre+inner-tube = 305g.
Difference here is: 45g.
45+92.5 = 137.5g. That is pretty much the min. average difference. My experience is also that something like the Continental Competition is robuster than a Veloflex Master clincher.. Most people here will probably see a bit larger gap.
Many races have been won with people riding the last km on flat. Sometimes there is no time for a change. With clinchers there is no choice.
Imperial riders are faster, right?
Why. You mean there are no punctures or other kinds of tyre defects in races? Heck even on the track I've seen tyres fail-- even explode.
I don't use tape. I strongly advise against their use. But.. after a flat and a roadside repair or tyre swap.. With tubulars they are not 100%. But that does not say that they are horribly unsafe. For riding about I use something like Mastic One or Conti glue. How many time over the years have I struggled to remove one of those tyres when I got home to glue them correctly.
A patch kit would not have helped. The tyre (Continental) was completely trashed-- massive sidewall failure. I had a patch kit, some sealant, spare inner-tube and a mini-pump but no replacement tyre. When years ago I had total failure from a tubular (Vittoria) I just rode it home-- the tyre delaminated and so was a complete write-off.