Wassup, dawgs!? Today I swapped out my Michelin Pro 2 Race tyres that came with my bike about 6 months ago for a pair of dirt cheap Vittoria Rubino tyres, the brand/model that I have always used on previous bikes; touch wood, I have had very few pcres with the Rubinos over the years, certainly compared to other people I ride with - probably becuase they are so thick and heavy nothing can get through them!
Assuming all other factors are equal, same tyre pressure etc, what real world difference would I really see between these two tyre sets over say a 25 mile TT - 1 second? 10 seconds? 2 minutes? An hour??!!
Just popped over to analyticcycling.com, which Ive heard mentioned here before. If Im reading it right, and Im no scientist so Im probably not, they reckon a “premium clincher” has the lowest rolling resistance. Compared to this, using all the default settings (including 8m / second speed which I think is 28.8kph??), a “utility clincher” is 76 seconds slower over 40k. And a “touring clincher” is 150 seconds slower! It doesnt menion the weight factor, Ill go and have look…
(Some time later) Im back! But none the wiser. Couldnt understand what they were going on about…
IT sounds like you have a pretty good grasp on it. The weight is only going to matter much when accelerating or going uphill, shouldn’t have much effect on a flat TT
rolling resistance can be slightly subjective, but where you should feel a big difference is in the cornering.
I have ridden both the vittorias and the michelins,
the michelins (my current race tyre of choice) feel like they are locked to the road during tight fast corners, but don’t slow me down on the straights.
much smoother feeling in a straight line.
apparently there are slower and faster tires out there, but i can never tell that (well, not btwn the different 700x23 tires at roughly the same pressure). but they do have a very different feel on the road.
whether one feel is better than the other, or whether that difference is worth paying more, is fairly subjective.
If I were forced to place a bet, knowing nothing about the Rubino, I’d hazard about 30 seconds max. It depends on how flexible the sidewalls and casings are. Thick strong tires prevent flats but also do not flex well, and you have to flex that tire as you spin it around, hence increased rolling resistance.
I did an experiment in my parking garage once (enclosed…no wind). Setup A was continental gatorskins (28C) with a super thick “thorn proof” innertube. Setup B was Michelin Pro Race with a thin buytl tube. Setup C was a 650C bike with Veloflex Record tubulars. There was a HUGE difference between A and either of the others in terms of rolling distance. B was better than C by enough to be outside the margin of error. I believe the innertube was the main contributer to the poor performance of A.
rolling resistance can be slightly subjective, but where you should feel a big difference is in the cornering.
I have ridden both the vittorias and the michelins,
the michelins (my current race tyre of choice) feel like they are locked to the road during tight fast corners, but don’t slow me down on the straights.
much smoother feeling in a straight line.
I think you mean that rolling resistance is a tough thing to “feel”, right? As others have pointed out, it’s not subjective since it’s measureable.
Here’s a tip, if you want a better ability to “feel” the differences in rolling resistance between tires, just run them on some rollers and note whether they feel harder or easier to turn for the same wheel speed. Due to the extra distortion in the contact patch, rollers tend to have a “magnifying” effect on the rolling resistance of a factor of ~4X - 5X depending on the roller size. This means that the DIFFERENCES are magnified as well. I used this technique to effectively convince an “old skewl” racer that quality clinchers were as fast, or faster than his beloved tubulars. YMMV
“Cornering”, on the other hand, IS “slightly subjective”…
If you want to feel rolling resistance put on some Specialized Armadillos - they are just unbelievably slow, its like riding with the brakes on (i even checked this several times…)
