Re: Rolling Resistance

Mark J cleary <mcleary08@comcast.net> wrote:

On 6/21/2025 3:08 AM, Roger Merriman wrote:

AMuzi <am@yellowjersey.org> wrote:

On 6/20/2025 6:04 PM, Frank Krygowski wrote:

On 6/20/2025 4:34 PM, cyclintom wrote:

If you scan the rolling resistance chart all of the lowest
rolling resistance is on 25 mm tires. What that implies is
that the drum is entirely out of sync with the real world
since wider tires with lower pressures are both faster and
less likely to puncture. It is time fore the rolling
resistance people to redesign their setups to have more
connection to reality. My speed after two weeks off of the
bike with 32 mm tires is half a mph faster than riding a
lot on 28's

 
I'm going to shock people by agreeing with you on one point.
I do think the current test rigs for rolling resistance need
serious improvement. I've mentioned that before.
 

 
+1
A long time complaint here on RBT beginning with Mr Brandt
long ago.  Steel drum tests can be very accurately measured
but what they measure leaves a void between that and our
actual world.
 

Particularly the small drums and smooth drums that
bicyclerollingresistance.com uses hence its data doesn’t correlate that
well to MTB tyres in particular.
 
Silverstone has a much bigger drum with all sorts of surfaces, that folks
like Dylan Johnson have used to test tyres (MTB) which has correlated with
his real world testing so is bit more faith in that drum and set up, but
even so that it’s a hugely simplified model of the world must be accounted
for plus is one’s goal just speed?
 
Certainly off road even if one wants to ride fast, a fast rolling tyre
isn’t always your friend, the Thunderburts which are light with out much
tread are popular as fast tyres be that Gravel or XC but they are very much
terrain specific!
 
Even in mid summer descending on the steep grassy slope off the top of the
mountain to my folks place, with those you’d be running wide on the turns
in any other season you’d not make the turn!
 
Roger Merriman

 
I remember saying I got a lot miles on my tires compared to what others
were getting and Mike Jacoubosky say it was because I did not climb. He
said that climbing will wear tires out more. Mike is a Trek store owner
in Redwood California and I respect is opinions but generally would
disagree with this. I can see that going up long grades you go slower
turnover and possible some more tire wear but nothing like seemed to
imply. His implication was climbing is hard on tires.
 

Going up your going to be putting more load on the sidewalls and more
weight on the rear than on the flat, but not convinced that would be
enough, weight certainly does make a difference I get about 5/6K for the
front tyres vs 2K for the rear on the Gravel bike, which has similar wear
patterns to road bikes I used to own.

Ie weight does make a difference but unless your normal riding is up some
large hill ie 10-20 something miles, even then i suspect that road surfaces
ie hilly roads tend to be rough abrasive surfaces due to the
terrain/climate.

Equally folks like myself who are heavier I’m 92Kg /14 stone 7lb or 200lb
or thereabouts I can’t be bothered to do the calculations but I don’t
appear to trash tyres any quicker than my riding companions who are all
lighter some by quite some margin.

Roger Merriman