28 vs 32 tire

Until last year, I have been riding a comfort bike. This year I bought a
Fuji touring bike and have enjoyed the lower rolling resistance on the
700x32 tires. I'm wondering if I'll notice much reduction in the
rolling resistance if I move to a 700x28 tire.

Your advice will be appreciated.

Doug


--
greypilgrim_oh

greypilgrim_oh wrote:
Until last year, I have been riding a comfort bike. This year I bought a
Fuji touring bike and have enjoyed the lower rolling resistance on the
700x32 tires. I'm wondering if I'll notice much reduction in the
rolling resistance if I move to a 700x28 tire.

Your advice will be appreciated.

Doug

Probably you will notice because of the tread design, not from the size
alone. There are some really good 28c road tires out there for not a
lot of $, try one. Conti Sport series are nice tires for about $15 per.

On Tue, 23 Aug 2005 21:38:00 +1000, greypilgrim_oh
wrote:


Until last year, I have been riding a comfort bike. This year I bought a
Fuji touring bike and have enjoyed the lower rolling resistance on the
700x32 tires. I'm wondering if I'll notice much reduction in the
rolling resistance if I move to a 700x28 tire.


As it happens, I have a Fuji Touring Series also. Coincidentally I
also happen to have a pair of 700 x 32s (Michelin Tracers) and 700 x
28s (Conti Super Sports) which I interchange. I put on the 32s when
I'm planning to ride on unpaved trails, for example the crushed
limestone surfaces of the Katy Trail in Missouri or the Illinois
Prairie Path. The 28s are for pavement.

I just got back from cycling in Summit County, Colorado, exclusively
on paved trails and roads. I had the 32s mounted and forgot to change
tires before I left. I honestly couldn't detect any real difference.


jeverett3ATearthlinkDOTnet http://home.earthlink.net/~jeverett3

On Tue, 23 Aug 2005 14:38:57 GMT, John Everett
wrote:

On Tue, 23 Aug 2005 21:38:00 +1000, greypilgrim_oh
wrote:


Until last year, I have been riding a comfort bike. This year I bought a
Fuji touring bike and have enjoyed the lower rolling resistance on the
700x32 tires. I'm wondering if I'll notice much reduction in the
rolling resistance if I move to a 700x28 tire.


As it happens, I have a Fuji Touring Series also. Coincidentally I
also happen to have a pair of 700 x 32s (Michelin Tracers) and 700 x
28s (Conti Super Sports) which I interchange. I put on the 32s when
I'm planning to ride on unpaved trails, for example the crushed
limestone surfaces of the Katy Trail in Missouri or the Illinois
Prairie Path. The 28s are for pavement.

I just got back from cycling in Summit County, Colorado, exclusively
on paved trails and roads. I had the 32s mounted and forgot to change
tires before I left. I honestly couldn't detect any real difference.


jeverett3ATearthlinkDOTnet http://home.earthlink.net/~jeverett3

Dear John,

Hmmm . . . The highest point in Illinois is Charles Mound at
1135 feet. The highest point in Missouri is Taum Sauk
Mountain at 1772 feet.

Summit County, Colorado, enjoys an altitude of about 9,000
feet around popular Dillon Reservoir:

http://www.topozone.com/map.asp?lat=39.6&lon=-106.01667

So let's start with the defaults for a "roadster" with
"robust" tires at 1150 feet on this handy calculator and
vary the tires and elevation:

http://www.kreuzotter.de/english/espeed.htm

bike elev. tires mph
---- ---- ----- ---
roadster 1150 robust 14.8 Illinois
roadster 9000 robust 16.2 Colorado

roadster 1150 medium 15.7 Illinois
roadster 9000 medium 17.2 Colorado

The predicted improvement due to reduced wind drag at higher
altitude is about 50% more than the improvment due to
reduced rolling resistance with the better tire.

(I gain about 1 mph at 5,000 feet, but carefully forget to
mention this advantage when talking to sea-level friends.)

In theory, the same effort that propels us at 14.8 mph in
Illnois at around 1150 feet will make us go about 10% faster
(16.2 mph) on vacation at 9,000 feet in Colorado when we use
the same chubby tires.

Whether we'd notice such speed differences is another
matter. Without instruments, a solo rider cannot hope to
detect most of the speed differences debated on
rec.bicycles.tech.

In this case, there are other reasons why speeds in Colorado
may not seem any different than speeds near the Mississipi.
For one thing, we may not be putting out as many watts if
we're not used to 9,000 feet. Another problem is that Summit
County is likely to have more and steeper hills than
Illinois and Missouri, so there might not be any real
comparison. Finally, few of us spend a vacation in Colorado
staring at odometers and stop-watches.

Carl Fogel

wrote:
On Tue, 23 Aug 2005 14:38:57 GMT, John Everett
wrote:

On Tue, 23 Aug 2005 21:38:00 +1000, greypilgrim_oh
wrote:


Until last year, I have been riding a comfort bike. This year I bought a
Fuji touring bike and have enjoyed the lower rolling resistance on the
700x32 tires. I'm wondering if I'll notice much reduction in the
rolling resistance if I move to a 700x28 tire.


As it happens, I have a Fuji Touring Series also. Coincidentally I
also happen to have a pair of 700 x 32s (Michelin Tracers) and 700 x
28s (Conti Super Sports) which I interchange. I put on the 32s when
I'm planning to ride on unpaved trails, for example the crushed
limestone surfaces of the Katy Trail in Missouri or the Illinois
Prairie Path. The 28s are for pavement.

I just got back from cycling in Summit County, Colorado, exclusively
on paved trails and roads. I had the 32s mounted and forgot to change
tires before I left. I honestly couldn't detect any real difference.


jeverett3ATearthlinkDOTnet http://home.earthlink.net/~jeverett3

Dear John,

Hmmm . . . The highest point in Illinois is Charles Mound at
1135 feet. The highest point in Missouri is Taum Sauk
Mountain at 1772 feet.

Summit County, Colorado, enjoys an altitude of about 9,000
feet around popular Dillon Reservoir:

http://www.topozone.com/map.asp?lat=39.6&lon=-106.01667

So let's start with the defaults for a "roadster" with
"robust" tires at 1150 feet on this handy calculator and
vary the tires and elevation:

http://www.kreuzotter.de/english/espeed.htm

bike elev. tires mph
---- ---- ----- ---
roadster 1150 robust 14.8 Illinois
roadster 9000 robust 16.2 Colorado

roadster 1150 medium 15.7 Illinois
roadster 9000 medium 17.2 Colorado

The predicted improvement due to reduced wind drag at higher
altitude is about 50% more than the improvment due to
reduced rolling resistance with the better tire.

(I gain about 1 mph at 5,000 feet, but carefully forget to
mention this advantage when talking to sea-level friends.)

In theory, the same effort that propels us at 14.8 mph in
Illnois at around 1150 feet will make us go about 10% faster
(16.2 mph) on vacation at 9,000 feet in Colorado when we use
the same chubby tires.

Whether we'd notice such speed differences is another
matter. Without instruments, a solo rider cannot hope to
detect most of the speed differences debated on
rec.bicycles.tech.

In this case, there are other reasons why speeds in Colorado
may not seem any different than speeds near the Mississipi.
For one thing, we may not be putting out as many watts if
we're not used to 9,000 feet. Another problem is that Summit
County is likely to have more and steeper hills than
Illinois and Missouri,

No. Missouri has steeper hills than Colorado. Colorado has much
longer and higher hills/mountains than Missouri. But not steeper. BAM
riders can attest to the hilliness of Missouri's northern counties.
And the Ozarks in the southern half are very hilly.



so there might not be any real
comparison. Finally, few of us spend a vacation in Colorado
staring at odometers and stop-watches.

Carl Fogel

On 23 Aug 2005 12:23:23 -0700,
wrote:

he crushed
limestone surfaces of the Katy Trail in Missouri or the Illinois
Prairie Path.

Dear Russell,

Er, ignoring whether some bicycle rides in the Rocky
Mountains may be somewhat longer and steeper than some rides
in the delightful Ozarks, the context was:

" . . .the crushed limestone surfaces of the Katy Trail in
Missouri or the Illinois Prairie Path."

Possibly the Katy Trail of Missouri is a ride of such
fearsome grade that it would make Jobst fit training wheels
before attempting the ascent, but somehow it didn't sound
like that, sitting next to the modest and unassuming Prairie
Path of Illinois.

With luck, someone will track down a topo map of the Katy
Trail and I'll learn where T.S. Eliot could have gone riding
if he hadn't wandered across the Atlantic.

Carl Fogel

Since the KATY trail is a converted rail line that runs East-West
across the middle of Missouri, I'd guess that it's maximum grade would
be somewhere around 2%, and its average altitude somewhere around 500
feet above sea level.
As for Colorado vs. Missouri hills, having grown up in SW Missouri &
ridden some in Summit County, I'd agree with Russell Seater. Colorado
wins hands down on length of climbs and probably overall difficulty,
but I'd bet its much, much easier to find paved roads of any grade 12%
or above in Missouri than Colorado--us Hillbillies laid out our paths
long before them horseless carriages came along. But then LBJ gave us
'lectricity, and now they's pavin' all the hollows (rhymes with
collars).
--matt.

On 23 Aug 2005 12:57:37 -0700, "Matt"
wrote:

Since the KATY trail is a converted rail line that runs East-West
across the middle of Missouri, I'd guess that it's maximum grade would
be somewhere around 2%, and its average altitude somewhere around 500
feet above sea level.
As for Colorado vs. Missouri hills, having grown up in SW Missouri &
ridden some in Summit County, I'd agree with Russell Seater. Colorado
wins hands down on length of climbs and probably overall difficulty,
but I'd bet its much, much easier to find paved roads of any grade 12%
or above in Missouri than Colorado--us Hillbillies laid out our paths
long before them horseless carriages came along. But then LBJ gave us
'lectricity, and now they's pavin' all the hollows (rhymes with
collars).
--matt.

Dear Matt,

I'm intrigued and willing to learn.

Here's a convenient list of over 100 of Missouri's highest
spots, each with a link to Topozone:

http://americasroof.com/highest/mo.shtml

(If nothing else, people can use the site to find long lists
of links to high spots in various states.)

Can you use it (or any other internet map site) to find some
of these paved Missouri roads that run 12% grade or steeper?
How long are they?

At 12% grade, a road climbs about 633 feet in a mile.

The lowest point in Missouri is 205 feet above sea level,
down in the little tail of the state where the St. Francis
river enters Arkansas from Dunklin County, about 90 miles
from the highest point, Taum Sauk Mountain, 1772 feet:

http://www.conservation.state.mo.us/.../1999/3/42.htm

So the longest (purely theoretical) 12% grade in Missouri
would be from 205 to 1772 feet, a rise of 1567 feet in 2.47
miles.

Carl Fogel

On Tue, 23 Aug 2005 23:27:37 -0600,
wrote:

On 23 Aug 2005 12:57:37 -0700, "Matt"
wrote:

Since the KATY trail is a converted rail line that runs East-West
across the middle of Missouri, I'd guess that it's maximum grade would
be somewhere around 2%, and its average altitude somewhere around 500
feet above sea level.
As for Colorado vs. Missouri hills, having grown up in SW Missouri &
ridden some in Summit County, I'd agree with Russell Seater. Colorado
wins hands down on length of climbs and probably overall difficulty,
but I'd bet its much, much easier to find paved roads of any grade 12%
or above in Missouri than Colorado--us Hillbillies laid out our paths
long before them horseless carriages came along. But then LBJ gave us
'lectricity, and now they's pavin' all the hollows (rhymes with
collars).
--matt.

Dear Matt,

I'm intrigued and willing to learn.

Here's a convenient list of over 100 of Missouri's highest
spots, each with a link to Topozone:

http://americasroof.com/highest/mo.shtml

(If nothing else, people can use the site to find long lists
of links to high spots in various states.)

Can you use it (or any other internet map site) to find some
of these paved Missouri roads that run 12% grade or steeper?
How long are they?

At 12% grade, a road climbs about 633 feet in a mile.

The lowest point in Missouri is 205 feet above sea level,
down in the little tail of the state where the St. Francis
river enters Arkansas from Dunklin County, about 90 miles
from the highest point, Taum Sauk Mountain, 1772 feet:

http://www.conservation.state.mo.us/.../1999/3/42.htm

So the longest (purely theoretical) 12% grade in Missouri
would be from 205 to 1772 feet, a rise of 1567 feet in 2.47
miles.

Carl Fogel

Horrors!

The lowest points section here . . .

http://americasroof.com/lowest.shtml

.. . . indicates that the low point of Missouri is actually
around 230 feet, more than 10% higher than the paltry 205
feet that I innocently believed.

So the longest (purely theoretical) 12% grade in Missouri
would be from 230 to 1772 feet, a rise of 1542 feet in 2.43
miles.

Whew! Now I can sleep tonight.

CF

Qui si parla Campagnolo Wrote:[color=blue]
greypilgrim_oh wrote:
Probably you will notice because of the tread design, not from the
size
alone. There are some really good 28c road tires out there for not a
lot of $, try one. Conti Sport series are nice tires for about $15 per.

Have you any experience with the new Rolly Polly tires, and how they
might compare with the Conti Sport Series?

Doug


--
greypilgrim_oh