Re: fast tires

cyclintom <cyclintom@yahoo.com> wrote:

On Thu Jun 12 14:32:57 2025 Zen Cycle  wrote:

On 6/12/2025 12:38 PM, Mark J cleary wrote:

On 6/12/2025 7:19 AM, Roger Merriman wrote:

cyclintom <cyclintom@yahoo.com> wrote:

People seem to think that fast tires have low rolling resistance but
that
is hardly the case In the rolling resistance tests 25 mm tires have
lower
rolling resistance than 28's. And high pressure 23 mm lower still,
Remember that they claim that their setup has bumps etc to correct
rolling resistace for road conditions but that can't be the case.
 

Whose tests? Drum tests particularly one with smaller drums will give a
less realistic model of tarmac.
 

Vittoria Corsa is rated as lowest rolling resistance but in my
experience
Michelin Pro5's are faster. Also I find that setting pressure below the
Silca pressure calculator increases the speed if not taken to extremes.
 

Both are designed to be fast road tyres, so you?d expect fairly close
performance between brands. And road is much more homogeneous than gravel
or MTB
 

I find TPU innertubes to be unbelievably expensive and flat very easily.
I see no advantage to them. While Latex tubes do increase speed, they
have to be pumped up every ride. In cold weather I can ride a butyl tube
for a week before pumping them up again.
 

In my relatively short experience of TPU tubes, is that they offer same
amount of puncture resistance aka zero if it gets through the tyre, it?s
game over.
 
They do feel noticeably nicer vs Butyl tubes, are yes more expensive and
more tedious to fix, though that would depend on how many punctures
someone
gets I used to get 1 every year or less. So it?s a 10 over a year at
worst.
 

Tubeless is nasty to work with. The tires are more expensive and
harder to mount.

 
Absolutely can be, the ongoing maintenance is why I run it on one bike
and
not all of them. While I?m a fan it?s not the best option 100% of the
time.

 
The informaion we are being fed is lacking accuracy and incomplete
leaving you to have to experiment yourself.
 

As with life need to fact check and be sure one understands let alone
that
for example tyre choices for example for my gravel bike each ride I do
would favour different tyre choices.
 
I?m fairly sure that for my uses bigger tyres into XC MTB sizes would
perform better for me most of the time.
 
Roger Merriman
 

 
I ride faster on my 25mm road bike Conti GP5000
s on the rim brake Habanero. I ride slower on the 32MM Conti's I have on
the disc brake Habby. I have no stats or ways to measure except how fast
I ride on any given ride. Lately the fatter 32 mms seem to me to be a
bit heavy and roll with more balancing require by me. I have no idea why.
 

 
It may have something to do with the road surface. One reason 32s can be
faster than 25s is if the road surface is on the rough side. If you've
been riding on new pavement lately, the 32's don't offer much advantage.
 
 
Of course inflation pressures have a lot to do with it. You might want
to experiment with the pressures, and don't forget to consider that your
gauge may be off too. The pump I keep in my car pump somehow become
offset by 20 PSI with no warning. I should just toss it because I have
three more floor pumps that are all good, I just have a real hard time
throwing away usable cycling parts and equipment (Much to my wife's
chagrin).
 
It sounds as if you're running the 32s somewhat underinflated. Put
another 10 PSI in and see what you think.

 
 
 
 
If you look these tires up on trhe rolling resistance site, 25 mm tires
at 100 psi are VERY low rolling resistance and as the tires get wider the
rolling resistance goes up pretty drmatically. But out riding on real
somewhat crackled pavement the wider tires come into their own. Riding
over logitudinl cracks I couldn't feel a thing while with 25's it would
try to jerk the bars out of my hands. There are some places on these
routes where the whole road is nothing but cracks with the pavgement
broken into hexigons for 50 feet of so. With 32's Gatorhardshells I could
feel it but it had no effect on the direction of the bike which wasn't
the case with 28 mm Vittoria Corsa's. So it would be nice if I could out
these wide tires on the bikes I usually ride.
 

Get a newer frame with clearance for 32mm or more and build it up?

Which is what I have settled I think for the new Gravel bike for a
significant birthday incoming aka Frameset as I have a decent groupset and
wheelset on the gravel bike it’s mainly the limited tyre clearance as it
was one of the earlier gravel bikes.

And I want the capacity to run big tyres even XC MTB ones at a push.

Roger Merriman