Tires, rolling resistance and lightness - empirical lesson learned.
Jay LePree
Here is one data point, that may save you some money. I typically
ride either Michelin Dynamics, Ruffy Tuffys, or Panaracer Pasela Tour
Guards. They have all worked well for me. I wanted to get some new
tires for a 97 Carrera that I ride as I wore out the Dynamics I had
on it.
I was in my local bike store, the employees of which always give great
advice. I took the recommendation to purchase the Continental Grand
Prix 4000's (700 x 25 mm). They are really nice tires with regards to
their lightness and their seemingly toughness. (I ran through glass
when I was not paying attention. I had two chunks stick in the tire
but not penetrate the "Vectran" belt.)
The tires did not however make me any faster, and I really cannot
sense a difference in ride quality. (This despite their apparent
lightness, their rolling resistance, and their TPI count and supple
sidewalls.) For the price I paid for them, I was hoping that I would
sense a difference, but I can't. I don't regret buying them because
they are nice tires, but once they wear out, I will go back to my less
expensive choices because they seem to work just as well.
Best regards to all,
Jay
Demarest, NJ
Angus
I'm sure many riders can pick up the differences, but the only time I
have been able to "detect" a rolling resistance difference in tires
has been either: after a big change (25mm to 35mm) or when one of the
tires was a real dog. Cornering stability (especially on dirt) is
more noticable to me. It has been, however, quite easy to detect a
flat...
Angus
Bruce
Bruce
Mojo
the ride; perhaps it was subtly different than my RollyPoly/Ruffy/
Tuffy tires. But here in western Colorado, the goatheads really loved
the Grand Bois. I suffered 3 flats in as many weeks, which is 1 more
than the last 2 years of riding the RP/RT. So now I am back on my RP/
RT setup with nary a flat in the last year. Life is Good. Great
morning ride into the Colorado National Monument http://www.nps.gov/colm/
Now its garden time.
rswa...@nyx.net
years but have mostly been on Grand Bois the last year. Despite a run
of bad luck the first week on the GBs, the overall puncture rate is
the same. I ride in goat head country (including the CO monument.
Awesome ride!!) I've come to the conclusion that goatheads don't care
what tires I've got, so I might as well ride the ones that feel the
best.
Ryan
NickBull
it is that some tires that are empirically faster feel "slower". His
theory is that (regardless of the tire) as we speed up, more road
noise is transmitted through the tire and up to our hands, feet and
butt. So we associate speed with that vibration. So given two tires
with similar rolling resistance, the "buzzier" tire will feel faster,
even if it is empirically slower, while the empirically faster but
smooth-rolling tire feels "slower".
I don't know how you do a double-blind, scientifically valid test of
this theory, but it seems pretty reasonable.
One more data point on Grand Bois and Pasela's: I've run GB 700x30
tires for about a year, maybe four or five thousand miles with one
flat. I'll still run them for "important" brevets, but for run-of-the-
mill riding, I find the Pasela 700x32 wire-bead non-TourGuard tires
feel "just as fast" and if anything are a bit plushier.
Optimal tire pressures to get a 15 percent "drop", given my weight and
its distribution, are: for the GB, 71 psi front, 101 psi rear; and for
the Pasela's, 62 psi front and 89 psi rear. That's with a measured
108 pound load on the front wheel and 152 on the rear.
On May 19, 3:59 pm, rswat...@nyx.net wrote:
> Just another data point: I rode Ruffy Tuffies exclusively for many
> years but have mostly been on Grand Bois the last year. Despite a run
> of bad luck the first week on the GBs, the overall puncture rate is
> the same. I ride in goat head country (including the CO monument.
> Awesome ride!!) I've come to the conclusion that goatheads don't care
> what tires I've got, so I might as well ride the ones that feel the
> best.
>
> Ryan
>
>
>
>
>
>
> > I put some Grand Bois 700Xtrue 28 tires on my Rivendell road. I liked
> > the ride; perhaps it was subtly different than my RollyPoly/Ruffy/
> > Tuffy tires. But here in western Colorado, the goatheads really loved
> > the Grand Bois. I suffered 3 flats in as many weeks, which is 1 more
> > than the last 2 years of riding the RP/RT. So now I am back on my RP/
> > RT setup with nary a flat in the last year. Life is Good. Great
> > morning ride into the Colorado National Monumenthttp://www.nps.gov/colm/
>
> - Show quoted text -
rswa...@nyx.net
On May 20, 2008, at 10:41, NickBull <nick.bi...@gmail.com> wrote:
>
> In the most recent issue of Bicycle Quarterly, Jan Heine discusses why
> it is that some tires that are empirically faster feel "slower". His
> theory is that (regardless of the tire) as we speed up, more road
> noise is transmitted through the tire and up to our hands, feet and
> butt. So we associate speed with that vibration. So given two tires
> with similar rolling resistance, the "buzzier" tire will feel faster,
> even if it is empirically slower, while the empirically faster but
> smooth-rolling tire feels "slower".
>
> I don't know how you do a double-blind, scientifically valid test of
> this theory, but it seems pretty reasonable
>>
>>
>>
To me, smooth and quiet feels fast, while noise and road buzz feel
slow and inefficient. Probably all in my head, but I choose the comfy
and "fast feeling" ones every time.
Ryan
Tim McNamara
On May 20, 2008, at 11:41 AM, NickBull wrote:
> In the most recent issue of Bicycle Quarterly, Jan Heine discusses why
> it is that some tires that are empirically faster feel "slower". His
> theory is that (regardless of the tire) as we speed up, more road
> noise is transmitted through the tire and up to our hands, feet and
> butt. So we associate speed with that vibration. So given two tires
> with similar rolling resistance, the "buzzier" tire will feel faster,
> even if it is empirically slower, while the empirically faster but
> smooth-rolling tire feels "slower".
>
> I don't know how you do a double-blind, scientifically valid test of
> this theory, but it seems pretty reasonable.
It's a really interesting question and could probably provide
material for a doctoral thesis. There are a number of known cues
that we use to perceive velocity that have been described in
perceptual psychology literature (particularly J.J. Gibson and his
successors). For example:
http://www.interdisciplines.org/enaction/papers/3/8
Visual cues are important, including the rate of approach to
stationary objects (judging the changing gap), the rate of expansion
of the apparent size of the object in the visual field, the apparent
speed of the texture of the ground passing under us, etc. We use
auditory cues, for example higher frequency sounds (e.g. the tire on
the pavement) indicating higher speed. And we use tactile cues like
Nick mentions. Any of these cues can be fooled, of course- video
games and driving simulators do it as a matter of course. The large
scale principles are consistent and mathematically describable; the
neurology is still obscure.
In the case of rating how fast the tires feel compared to other
tires, I also think we rate how "nervous" the bike feels. A tire
that provides a lot of damping, so that the bars don't swing back and
forth as easily at low speeds, will probably feel faster. At least
when I hop on a bike and at low speeds the bars can be easily swung
back and forth at parking lot speeds, I have the sense that the bike
will be "fast" and "maneuverable."
charlie
25mm at 120 psi. I thought I would be faster and I wasn't. I ride road
tires from 40 mm to 25mm and at 260 pounds I like my widest tires the
best. The fastest rollers have been my 700x30mm Panaracer Urbanmax
tires at 90 spi. Maybe at my weight I need a certain amount of volume
similar to a semi truck when it carries a heavy load. While my 40mm
Schwalbe Marathons are the most comfortable and secure they do seem
slower accelerating. Hard skinny tires seem fast but my times don't
show it significantly. Go wide with pride.