GreenPlease wrote:
Tom A. wrote:
rruff wrote:
The Speed looks to be Vittoria Diamante based with the 220tpi nylon casing... with no protection belt. Good for low Crr, not so good for punctures. Even the Diamante *with* an extra layer was pretty poor for that.
Might be pretty decent for TTs if the aero is good. Unfortunately no size smaller than 23...
That was my concern as well...but after putting quite a bit of miles on each model, I have to say that even the Speed models appear fairly durable...more so than my experiences with the Diamantes and other tires based on that casing. The compound feels different and more cut resistant, and the amount on the sidewalls seems slightly thicker as well, which could also possibly improve cut resistance.
As a tangent, would I be incorrect in saying that many tire manufacturers skimp on the sidewalls in an effort to keep tire weight down? Thicker sidewall tread shouldn't really impact crr, correct?
It's funny you should ask that...when I was sent the final production candidates to test, there was an odd result with the 23C version of the Speed model actually rolling slightly faster than the 25C. After a bit of digging and comparing numbering on the tires, we realized that I had happened to be sent a different proto version of the 25C with slightly thicker rubber on the sidewalls. Now, this difference is something that one couldn't even perceive just looking at the tires and holding them in your hand.
Anyway, that was the result that is holding up the release of the Crr data. I have a 25C Speed coming to me as we speak.
So yes, sidewall material DOES matter in regards to Crr (along with tread thickness, rubber compounds, width, and puncture belts)
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