Changing 700cm tire widths

[Paul]

Hi All,

I just bought a new road bicycle, and it came with 700 x 25 tires. I
ride a lot on country roads, so many of them are of the tar/chip
variety. Could I change to a wider tire and maybe get a better ride?
If not, would it be advantageous to get a different width tire just
for the sake of durability?
If there is no possible, conceivable reason to switch tire widths, how
about a different type of the same size tire I have now? Right now, I
have "Bontrager select" (stock Trek) tires.
Suggestions, anyone?

As always, thanks a lot!

Paul

 

[David L. Johnson]

On Wed, 17 Aug 2005 03:39:23 +0000, Paul wrote:

> Hi All,
>
> I just bought a new road bicycle, and it came with 700 x 25 tires. I
> ride a lot on country roads, so many of them are of the tar/chip
> variety. Could I change to a wider tire and maybe get a better ride?
> If not, would it be advantageous to get a different width tire just
> for the sake of durability?
> If there is no possible, conceivable reason to switch tire widths, how
> about a different type of the same size tire I have now? Right now, I
> have "Bontrager select" (stock Trek) tires.

So, what's wrong with the tires you have? 25mm are actually fairly wide
these days, and should be pretty durable, even on chip-seal roads. It's
worth, at least, trying these tires to see how they last.

Modern road bikes will not likely clear anything larger than a 28mm
(real width) tire, and even that depends on the bike. Of course, stated
widths are often wider than reality, so maybe you can get a "28" in there.

--

David L. Johnson

__o | And though I have the gift of prophecy, and understand all
_`\(,_ | mysteries, and all knowledge; and though I have all faith, so
(_)/ (_) | that I could remove mountains, and have not charity, I am
nothing. [1 Corinth. 13:2]

 

[Earl Bollinger]

"Paul" <[email protected]> wrote in message
news:[email protected]...
> Hi All,
>
> I just bought a new road bicycle, and it came with 700 x 25 tires. I
> ride a lot on country roads, so many of them are of the tar/chip
> variety. Could I change to a wider tire and maybe get a better ride?
> If not, would it be advantageous to get a different width tire just
> for the sake of durability?
> If there is no possible, conceivable reason to switch tire widths, how
> about a different type of the same size tire I have now? Right now, I
> have "Bontrager select" (stock Trek) tires.
> Suggestions, anyone?
>
> As always, thanks a lot!
>
> Paul

You need to carefully check your bike to see if a wider tire will clear the
frame and brake calipers or not.
But going to 700c by 28's is very possible.
Most road bikes have the rear wheel up pretty close to the frame so a wider
taller tire may or may not clear.
Thus the bigger tires like 700c by 32 or 700c by 35 and so on may be too
wide or tall to clear the frame and brakes.

 

[mark]

"Paul" wrote ...
> Hi All,
>
> I just bought a new road bicycle, and it came with 700 x 25 tires. I
> ride a lot on country roads, so many of them are of the tar/chip
> variety. Could I change to a wider tire and maybe get a better ride?
> If not, would it be advantageous to get a different width tire just
> for the sake of durability?
> If there is no possible, conceivable reason to switch tire widths, how
> about a different type of the same size tire I have now? Right now, I
> have "Bontrager select" (stock Trek) tires.
> Suggestions, anyone?
>
> As always, thanks a lot!
>
> Paul

A wider tire would give a smoother ride and reduce the likelihood of pinch
flats (tube is pinched between tire and rim as bike hits a pothole, curb,
etc.). Don't know if the tire would last any longer, but there's been a few
threads about wheels for heavy riders where it was suggested that wider
tires would extend spoke life for large riders.

Check the clearance where the rear wheel passes between the chainstays and
where the front wheel passes through the fork, if you've got room for a
wider/taller tire then give it a try.
--
mark

 

[Booker C. Bense]

-----BEGIN PGP SIGNED MESSAGE-----

In article <[email protected]>,
Paul <[email protected]> wrote:
>Hi All,
>
>I just bought a new road bicycle, and it came with 700 x 25 tires. I
>ride a lot on country roads, so many of them are of the tar/chip
>variety. Could I change to a wider tire and maybe get a better ride?

_ What gives a better ride is actually lower air pressure in the
tire. Wider tires will give a better ride only if you run them at
lower air pressures. This is easier to do on wider tires since
you don't have as much risk of a pinch flat or rim damage. The
first thing I would suggest is taking at least 10psi out of your
tires, especially if you have then at the max listed on the
tire. Tire pressure should be proportional to your body/bike
weight and the size of the tire. Check this chart for a starting
point

http://www.sheldonbrown.com/tires.html#width


>If not, would it be advantageous to get a different width tire just
>for the sake of durability?
>If there is no possible, conceivable reason to switch tire widths, how
>about a different type of the same size tire I have now? Right now, I
>have "Bontrager select" (stock Trek) tires.

_ There are differences between tires of the same size, but IMHO not
enough to justify new tires until you wear these out, unless you
are having some other problem. I suspect that much of your
problem will be solved or at least greatly reduced by getting
the correct pressure.

_ Booker C. Bense



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[Dennis Ferguson]

Paul wrote:
> I just bought a new road bicycle, and it came with 700 x 25 tires. I
> ride a lot on country roads, so many of them are of the tar/chip
> variety. Could I change to a wider tire and maybe get a better ride?
> If not, would it be advantageous to get a different width tire just
> for the sake of durability?
> If there is no possible, conceivable reason to switch tire widths, how
> about a different type of the same size tire I have now? Right now, I
> have "Bontrager select" (stock Trek) tires.
> Suggestions, anyone?

Wider tires at lower pressure are pretty much always more comfortable. I
don't know about more durable, however, as this seems to depend a lot more
on how the tires are made and what they're made from.

Note that if you can't fit, or otherwise don't like, 28mm or larger tires,
you still might benefit from a different brand of 25mm tires. The 25mm
tires that come with some Trek bicycles that I've measured in bike shops
have been not much more than 23mm wide and are about the narrowest 700x25c
tires I've seen. Michelin 700x25c tires are about the widest I've measured,
at about 25mm when mounted and inflated. The few 700x28c tires I've
measured have been between 26mm and 27mm wide. Choosing from among the
different brands and sizes (and paying attention to the fact that the
widths of same-size tires will vary from brand to brand) should allow you
to find something which fills your frame to your liking.

Dennis Ferguson

 

[Chris Neary]

>_ What gives a better ride is actually lower air pressure in the
>tire. Wider tires will give a better ride only if you run them at
>lower air pressures. This is easier to do on wider tires since
>you don't have as much risk of a pinch flat or rim damage. The
>first thing I would suggest is taking at least 10psi out of your
>tires, especially if you have then at the max listed on the
>tire. Tire pressure should be proportional to your body/bike
>weight and the size of the tire. Check this chart for a starting
>point
>
>http://www.sheldonbrown.com/tires.html#width


Because of basic physics, the maximum allowable pressure for a wide tire
will always be lower than for a narrower tire of comparable construction.
Not reducing the pressure might result in a casing failure due to excessive
pressure stresses.

Another potential hazard of failing to use the recommended reduced pressures
in a wider tire is rim failure, but this is dependent on the design margins
of the rim.

Because many tires vary from their stated size, the potential effect of rim
width on actual tire volume, and inaccuracies in tire pump gauges, the
values in tables such as Sheldon's are most useful for comparison purposes,
and should not be considered "hard and fast" values, Sheldon basically says
as much.


Chris Neary
[email protected]

"Science, freedom, beauty, adventure: what more could
you ask of life? Bicycling combined all the elements I
loved" - Adapted from a quotation by Charles Lindbergh

 

[Paul]

On Wed, 17 Aug 2005 19:46:52 GMT, Dennis Ferguson
<[email protected]> wrote:

>Wider tires at lower pressure are pretty much always more comfortable. I
>don't know about more durable, however, as this seems to depend a lot more
>on how the tires are made and what they're made from.
>
>Note that if you can't fit, or otherwise don't like, 28mm or larger tires,
>you still might benefit from a different brand of 25mm tires. The 25mm
>tires that come with some Trek bicycles that I've measured in bike shops
>have been not much more than 23mm wide and are about the narrowest 700x25c
>tires I've seen. Michelin 700x25c tires are about the widest I've measured,
>at about 25mm when mounted and inflated. The few 700x28c tires I've
>measured have been between 26mm and 27mm wide. Choosing from among the
>different brands and sizes (and paying attention to the fact that the
>widths of same-size tires will vary from brand to brand) should allow you
>to find something which fills your frame to your liking.
>
>Dennis Ferguson


Thanks Dennis,

I do a lot of riding on tar and chip roads, and I want to do whatever
I can to make it better for me and the rims.

Paul