28 vs 32 tire

greypilgrim_oh said:

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.

greypilgrim_oh said:

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.

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

John Everett said:

greypilgrim_oh said:

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.

jeverett3<AT>earthlink<DOT>net 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

Quoted message said:

John Everett said:

greypilgrim_oh said:

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.

jeverett3<AT>earthlink<DOT>net 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

Quoted message said:

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, [email hidden]

Quoted message said:

he crushed

Quoted message said:

Quoted message said:

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.

Matt said:

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/kids/out-in/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, [email hidden]

Quoted message said:

Matt said:

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/kids/out-in/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 said:

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

Quoted message said:

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:

750 feet MSL would be much closer to the average elevation of the Illinois
Prairie Path.

--
Sniper Anon

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Sniper Anon said:

Quoted message said:

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:

750 feet MSL would be much closer to the average elevation of the Illinois
Prairie Path.

Dear Snip,

I expect that you're right and that 750 feet is more
accurate for Illinois.

But now let's plug your figure into the calculator and
insert the result in the original table:

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

bike elev. tires mph
---- ---- ----- ---
roadster 750 robust 14.7 snip's adjusted elevation
roadster 1150 robust 14.8 Illinois
roadster 9000 robust 16.2 Colorado

roadster 750 medium 15.6 snip's adjusted elevation
roadster 1150 medium 15.7 Illinois
roadster 9000 medium 17.2 Colorado

This illustrates how a 400-foot change in elevation (1150
versus 750 feet) barely shows up in a modest bicyling
example--the speed change registers as only a tenth of a
mile per hour, and that's probably due to lucky rounding.

It takes a rise of 7,850 feet to reduce wind drag enough to
add about 1.5 mph to a bicycle going about 15 mph. The
wind-drag reduction of a rise only roughly 1/20th of that
height is too small to measure reliably on a scale using
tenths of a mile per hour.

And of course the 9,000 foot figure for Summit County is the
elevation of the reservoir--most trails go up from there:

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

Note the nameless 9430-foot hill next to the reservoir. The
nearby mountains (5 miles away) run 10 to 12 thousand feet

So I think that the default Kreuzotter 1150-foot elevation
works well enough to show the wind-drag in both Illinois and
Missouri versus what may be expected in Summit County,
Colorado.

From Colorado, the elevations of Illinois and Missouri
resemble a who's-the-tallest-dwarf contest, just as Colorado
elevations amuse a doctor whom I know who grew up in the
shadows of the Himalayas.

Cheers,

Carl Fogel

Quoted message said:

From Colorado, the elevations of Illinois and Missouri
resemble a who's-the-tallest-dwarf contest, just as Colorado
elevations amuse a doctor whom I know who grew up in the
shadows of the Himalayas.

In the time it's taken for this thread to reach this point, a thread
started by my reference to our recent cycling outing in Summit County,
Colorado; we've traveled to New Hampshire and back. As an aside, we
did take our bikes with us and got in some riding in the Conway,
Tamworth, Sandwich areas.

However, to further illustrate Carl's point, our host on this latest
journey had a certificate on his wall attesting to his having
successfully scaled all the 4,000 footers in the White Mountains.
Sigh!

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

Quoted message said:

And of course the 9,000 foot figure for Summit County is the
elevation of the reservoir--most trails go up from there:

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

Note the nameless 9430-foot hill next to the reservoir.

Not nameless at all. I assume you're referring to Sapphire Point,
reached by bike up Swan Mountain Road. Perhaps not, since that's
listed as 9606' on my topo map.

Later...okay, I did check the above url. The point you're referring to
is indeed unnamed, even on my topo map; but note the road paralleling
the lake just to the north of the 9430' hill. That's Swan Mountain
Road, and at that particular spot dead straight and really downhill.
I've approached 50 mph coming down there, but last time suddenly
remembered I was on a 15 year old bike and decided some application of
brakes would be prudent.

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

John Everett said:

Quoted message said:

From Colorado, the elevations of Illinois and Missouri
resemble a who's-the-tallest-dwarf contest, just as Colorado
elevations amuse a doctor whom I know who grew up in the
shadows of the Himalayas.

In the time it's taken for this thread to reach this point, a thread
started by my reference to our recent cycling outing in Summit County,
Colorado; we've traveled to New Hampshire and back. As an aside, we
did take our bikes with us and got in some riding in the Conway,
Tamworth, Sandwich areas.

However, to further illustrate Carl's point, our host on this latest
journey had a certificate on his wall attesting to his having
successfully scaled all the 4,000 footers in the White Mountains.
Sigh!

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

Dear John,

To be fair, it sounds like an awful lot of hiking:

http://www.peakbagger.com/list.aspx?lid=21404

And 6,000+ feet of clean prominence isn't bad at all:

http://www.peakbagger.com/peak.aspx?pid=6960

The description makes Mount Washington sound cold,
miserable, and dangerous.

Brrr! Just thinking about it makes me want to go riding half
an hour early this evening, just to be safe and warm--with
the current cold snap, the temperature might drop below 70
before sunset.

Carl Fogl

Quoted message said:

John Everett said:

However, to further illustrate Carl's point, our host on this latest
journey had a certificate on his wall attesting to his having
successfully scaled all the 4,000 footers in the White Mountains.
Sigh!

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

Dear John,

To be fair, it sounds like an awful lot of hiking:

http://www.peakbagger.com/list.aspx?lid=21404

And 6,000+ feet of clean prominence isn't bad at all:

http://www.peakbagger.com/peak.aspx?pid=6960

The description makes Mount Washington sound cold,
miserable, and dangerous.

Brrr! Just thinking about it makes me want to go riding half
an hour early this evening, just to be safe and warm--with
the current cold snap, the temperature might drop below 70
before sunset.

Dear Carl:

As an aside, there's an annual bike race up the Mt. Washington auto
road. It was held just before we arrived in NH, and was all the news
in the local sports pages. Winner...tah-dah...Tyler Hamilton.

Guess the local organizers don't pay no mind to those furrin UCI
suspensions. ;-)

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3