The difference 1 Bar makes!!!

Mark A Poman said:

Been running my new Vittoria 700x23 Open Corsa CX Tires the last
couple of weeks at 7 Bar (100psi) I thought these seemed hard
(Ridewise), but decided for the heck of it, to up the poundage to 8
Bar (115psi) Man, what a difference!

OK. I'll bite. What is the difference and what is the benefit?

Quoted message said:

While most of my roads are on the horrible side around here anyway,
and I was worried about a much harder ride, I didn't really notice
too much difference in ride quality, but I sure did notice a
difference as far as rolling resistance was concerned. It certainly
seemed to take less effort to pedal, and keep a good pace with the
higher inflation pressures.

Are you sure you weren't experiencing a psychosomatic response? If
you look at RR graphs at:

http://www.terrymorse.com/bike/imgs/rolres.gif

You'll see that differences in RR are minuscule at those pressures.

Quoted message said:

I don't think I'll be going back to a lower setting! May try 120psi
next just for the heck of it?

I think you are also overlooking cornering, for which the contact
patch has become smaller and compliance of the tire to road texture
has become worse.

Jobst Brandt
[email hidden]

Hello Jobst, Thank you for your reply.

Honestly, there was a slight difference I could feel, and seemed that
acceleration/coming up to cruising speed was also a bit easier with
the higher (8 Bar )pressures.

Maybe you are right in a sense about imagining this quality, as every
time I ride, I see to be improving all the time, so perhaps each time
I ride, I am becoming stronger, and stronger, and this makes it feel
like it's easier to pedal? lol This might be a more real explanation?,
I don't know?

Since recommended inflation pressures are 7-9 Bar for this tire, I
figured why am I running at the low end, and wanted to try a bit more
pressure.

Will Tire adhesion be necessarily worse increasing pressure by 1 Bar
with this particular tire? Thank you again Jobst, Mark D.

[email hidden] wrote in message news:<[email hidden]>...

Quoted message said:

Mark A Poman said:

Been running my new Vittoria 700x23 Open Corsa CX Tires the last
couple of weeks at 7 Bar (100psi) I thought these seemed hard
(Ridewise), but decided for the heck of it, to up the poundage to 8
Bar (115psi) Man, what a difference!

OK. I'll bite. What is the difference and what is the benefit?

Quoted message said:

While most of my roads are on the horrible side around here anyway,
and I was worried about a much harder ride, I didn't really notice
too much difference in ride quality, but I sure did notice a
difference as far as rolling resistance was concerned. It certainly
seemed to take less effort to pedal, and keep a good pace with the
higher inflation pressures.

Are you sure you weren't experiencing a psychosomatic response? If
you look at RR graphs at:

http://www.terrymorse.com/bike/imgs/rolres.gif

You'll see that differences in RR are minuscule at those pressures.

Quoted message said:

I don't think I'll be going back to a lower setting! May try 120psi
next just for the heck of it?

I think you are also overlooking cornering, for which the contact
patch has become smaller and compliance of the tire to road texture
has become worse.

Jobst Brandt
[email hidden]

Mark D Poman said:

Since recommended inflation pressures are 7-9 Bar for this tire, I
figured why am I running at the low end, and wanted to try a bit
more pressure.

Quoted message said:

Will Tire adhesion be necessarily worse increasing pressure by 1 Bar
with this particular tire?

Unless you are one to corner, leaned over more than 40 degrees, I
don't think you'll find any change. 23mm tires aren't any good for
cornering anyway. They are too narrow to bridge bad traction spots
and too hard to have a sufficiently large contact patch.

Jobst Brandt
[email hidden]

Jobst, Just thinking some more about this, I was experiencing a
pressure gauge problem over the past couple weeks, and this may also
have influenced a possible erroneous reading previously?

I have not have been a 7 Bar before, and so, there may be the
possibility that I have gone to an increase greater than 1 Bar?

Just rode 20mi earlier with the tires at 120psi, and they performed
just fine.

Mark

[email hidden] (Mark) wrote in message news:<[email hidden]>...

Quoted message said:

Been running my new Vittoria 700x23 Open Corsa CX Tires the last
couple of weeks at 7 Bar (100psi) I thought these seemed hard
(Ridewise), but decided for the heck of it, to up the poundage to 8
Bar (115psi) Man, what a difference!

While most of my roads are on the horrible side around here anyway,
and I was worried about a much harder ride, I didn't really notice too
much difference in ride quality, but I sure did notice a difference as
far as rolling resistance was concerned. It certainly seemed to take
less effort to pedal, and keep a good pace with the higher inflation
pressures.

I don't think I'll be going back to a lower setting! May try 120psi
next just for the heck of it? Mark

(Mark) said:

Maybe you are right in a sense about imagining this quality, as every

BTW, if you're not sure if it's your imagination that the rolling
resistance is better, and it helps you enjoy your riding more, then
who cares whether it's real or imagined?
--
Rick Onanian

Mark said:

Been running my new Vittoria 700x23 Open Corsa CX Tires the last
couple of weeks at 7 Bar (100psi) I thought these seemed hard
(Ridewise), but decided for the heck of it, to up the poundage to 8
Bar (115psi) Man, what a difference!

Agreed. I find CX's sluggish at 7 bar. I have the front at 7.5 to 8, and
the rear at just over 8.5.

~PB