View Single Post
  #32  
Old September 2nd 19, 06:48 AM posted to rec.bicycles.tech
Tim McNamara
external usenet poster
 
Posts: 6,863
Default Rolling Resistence

On Wed, 28 Aug 2019 09:18:19 -0700 (PDT), Tom Kunich
wrote:
On Tuesday, August 27, 2019 at 9:22:23 PM UTC-7, Frank Krygowski
wrote:
On Tuesday, August 27, 2019 at 5:51:20 PM UTC-4, Tom Kunich wrote:
Because of several things, I ended up mounting the Vittoria Roubino
Pro G+ tires on the LeMond.

Sunday I did an easy 40 mile ride and I was exhausted at the end.
These tires did ride well - they smoothed out the roads quite a bit
th9ugh they appeared to have a lot of rolling resistance. I
couldn't figure out if it was my imagination and finally came to
the conclusion that I am simply on the low side of my fitness
cycle. The difference in rolling resistance is so small compared to
the wind resistance that I can't see how you could possibly tell.

I did a hard 40 miler today with a lot of climbing. I used the
Colnago which has the Vittoria tubeless racing tires on box
tubeless times. Now the Colnago is an aero bike but since this ride
is mostly all climbing or very twisty downhills the aero hardly
seems significant.

But I did 3400 feet of climbing and the tires seemed to make a
rather extraordinary difference. I DID NOT get good sleep last
night so it isn't as if I recovered.

I think that it would probably be a good project to make a rather
off-hand experiment on types of tires and how they seem to run and
ride.

Both of the Vittoria racing tires - the Corsa G+ And Corsa G2
tubeless feel very good. Better than the Michelin Pro4 Endurance
which is pretty good. All of these tires have good puncture
resistance which is necessary around here. I think that I'll pull
the Roubino Pro's off and replace them with a new set of Gatorskins
I have laying around. It's been so long since I've ridden
Gatorskins that I can't remember their rolling resistance.

On another set of wheels I did a couple of metrics on a set of
Continental GP5000TLR tubeless tires. I wouldn't exactly call these
things low rolling resistance. They have a tacky compound that
screws up any directional stability the tires may have. While the
bike goes exactly where you point it with the Vittoria Corsa G+ you
have to watch the GP5000's closely. But in a corner the Continental
is probably better. Riding these metrics I was often confronted
with a decreasing radius turns. On the Vittoria's I would slow a
little and complete the turn. With the Continentals I would just
ride through it.

My experience with the Continental tires is that you have to wear
them through to the thread before throwing them out. The Vittorias
are different. It didn't appear to have much wear on the tread
facing but the rubber sidewalls were peeling away and that made me
nervous so I threw them away.

I guess I'll have to experiment to see if the non-aero LeMond is
what the problem is or the rolling resistance of the tires.


Seems to me if you want to get a handle on the rolling resistance of
your various tires, you might find a hill with a long, gentle slope
and keep track of speed results when coasting down it.

I've done just a little of that. One thing it taught me was that it's
harder than it seems to gauge rolling resistance just by "feel."

- Frank Krygowski


Rolling test aren't accurate either because humidity, pressure and
wind make a far larger contribution than rolling resistance. The only
practical way is either pure feel or to make a testing machine which I
do not feel like doing.


Or read the tests at www.bicyclerollingresistance.com which might very
well include your tires of choice.
Ads
 

Home - Home - Home - Home - Home