Rim Width

My daughter has a 'cross' bike with 700C x 35 tires fitted. She asked me
if she could get narrower tires for less rolling resistance. I'd like to
know if it's just a matter of buying new tubes and tires or if rims
which can accomodate 3.5 cm tires are too wide for the 2.3 cm tires she
wants.

TIA.

Paul Cassel wrote:
My daughter has a 'cross' bike with 700C x 35 tires fitted. She asked me
if she could get narrower tires for less rolling resistance. I'd like to
know if it's just a matter of buying new tubes and tires or if rims
which can accomodate 3.5 cm tires are too wide for the 2.3 cm tires she
wants.

TIA.

It is just a matter of getting thinner tires, like 23c and thinner
tubes-no problem.

Paul Cassel Wrote:
My daughter has a 'cross' bike with 700C x 35 tires fitted. She aske
me
if she could get narrower tires for less rolling resistance. I'd lik
to
know if it's just a matter of buying new tubes and tires or if rims
which can accomodate 3.5 cm tires are too wide for the 2.3 cm tire
she
wants.

TIA.
http://sheldonbrown.com/tire-sizing.html#width
and the other tire article:
http://sheldonbrown.com/tires.html
As long as the rims aren't too wide and they can handle the highe
pressue, it will be fine. I would shoot for 28 mm tire width wit
smooth "tread" for lower rolling resistance and other desirabl
benefits

--
daveornee

daveornee wrote:
Paul Cassel Wrote:

My daughter has a 'cross' bike with 700C x 35 tires fitted. She asked
me
if she could get narrower tires for less rolling resistance. I'd like
to
know if it's just a matter of buying new tubes and tires or if rims
which can accomodate 3.5 cm tires are too wide for the 2.3 cm tires
she
wants.

TIA.

http://sheldonbrown.com/tire-sizing.html#width
and the other tire article:
http://sheldonbrown.com/tires.html
As long as the rims aren't too wide and they can handle the higher
pressue, it will be fine. I would shoot for 28 mm tire width with
smooth "tread" for lower rolling resistance and other desirable
benefits.


Thanks to both you and 'speaks Campy' for your quick responses.

-paul

Paul Cassel wrote:
daveornee wrote:

Paul Cassel Wrote:

My daughter has a 'cross' bike with 700C x 35 tires fitted. She asked
me
if she could get narrower tires for less rolling resistance. I'd like
to
know if it's just a matter of buying new tubes and tires or if rims
which can accomodate 3.5 cm tires are too wide for the 2.3 cm tires
she
wants.

TIA.


http://sheldonbrown.com/tire-sizing.html#width
and the other tire article:
http://sheldonbrown.com/tires.html
As long as the rims aren't too wide and they can handle the higher
pressue, it will be fine. I would shoot for 28 mm tire width with
smooth "tread" for lower rolling resistance and other desirable
benefits.


Thanks to both you and 'speaks Campy' for your quick responses.

-paul



Paul,

I recall a few years ago, Jobst Brandt did some extensive testing and
found that rolling resistance actually increases when tire width goes
below 28mm. I would guess that width doesn't have as much an effect on
rolling resistance as you'd think. I think the tire material and
construction and inflation pressure are more important.

I got a mountain bike cheap at a local police auction. It had fat,
knobby tires. The tires were so loud, I thought a truck was behind me
when I went downhill. I replaced them with 1.4 inch (35mm) slick tires
and inflated them to 100 psi. The bike now rides like a road racer. I'm
a very happy rider now.

Tom

Tom Reingold wrote:

Paul,

I recall a few years ago, Jobst Brandt did some extensive testing and
found that rolling resistance actually increases when tire width goes
below 28mm. I would guess that width doesn't have as much an effect on
rolling resistance as you'd think. I think the tire material and
construction and inflation pressure are more important.

I got a mountain bike cheap at a local police auction. It had fat,
knobby tires. The tires were so loud, I thought a truck was behind me
when I went downhill. I replaced them with 1.4 inch (35mm) slick tires
and inflated them to 100 psi. The bike now rides like a road racer. I'm
a very happy rider now.


That's interesting and opposite of what I've read (I'm new to this). My
daughter was grumped because I roll better than she. I'm on 23's while
she's on 35's. OTOH, she has a LOT of tread while I have almost slicks.
So there is a factor we didn't put in here.

I'll look for 28's with very smooth tread. My buddy who rides a mtn bike
with slicks says I'm faster than him because of my 23's. I'd LIKE to
think it's me and not the bike.

Is Brandt's work published on the Web somewhere? -paul

Paul Cassel Wrote:
Tom Reingold wrote:

Paul,

I recall a few years ago, Jobst Brandt did some extensive testin
and
found that rolling resistance actually increases when tire widt
goes
below 28mm. I would guess that width doesn't have as much an effec
on
rolling resistance as you'd think. I think the tire material and
construction and inflation pressure are more important.

I got a mountain bike cheap at a local police auction. It had fat,
knobby tires. The tires were so loud, I thought a truck was behin
me
when I went downhill. I replaced them with 1.4 inch (35mm) slic
tires
and inflated them to 100 psi. The bike now rides like a road racer
I'm
a very happy rider now.


That's interesting and opposite of what I've read (I'm new to this)
My
daughter was grumped because I roll better than she. I'm on 23's while
she's on 35's. OTOH, she has a LOT of tread while I have almos
slicks.
So there is a factor we didn't put in here.

I'll look for 28's with very smooth tread. My buddy who rides a mt
bike
with slicks says I'm faster than him because of my 23's. I'd LIKE to
think it's me and not the bike.

Is Brandt's work published on the Web somewhere? -paul
http://www.terrymorse.com/bike/rrdiscuss.html
is a discussion and some dated chart of dat

--
daveornee

wider the rim the less rolling resistance, but higher the aerodynamic
resistance. that's why the pros, use skinny rims, they're less aero.

Paul Cassel Wrote:
Tom Reingold wrote:My daughter was grumped because I roll better tha
she. I'm on 23's while she's on 35's. Rider weight has a lot to do with this. I'm probably 20-30 pound
heavier than my brother, and I always outroll him, on bike as well a
inlines. On skis/snowboard I outslide (?) him

--
dabac

Paul Cassel wrote:
Tom Reingold wrote:

Paul,

I recall a few years ago, Jobst Brandt did some extensive testing and
found that rolling resistance actually increases when tire width goes
below 28mm. I would guess that width doesn't have as much an effect on
rolling resistance as you'd think. I think the tire material and
construction and inflation pressure are more important.

I got a mountain bike cheap at a local police auction. It had fat,
knobby tires. The tires were so loud, I thought a truck was behind me
when I went downhill. I replaced them with 1.4 inch (35mm) slick tires
and inflated them to 100 psi. The bike now rides like a road racer.
I'm a very happy rider now.


That's interesting and opposite of what I've read (I'm new to this). My
daughter was grumped because I roll better than she. I'm on 23's while
she's on 35's. OTOH, she has a LOT of tread while I have almost slicks.
So there is a factor we didn't put in here.

I'll look for 28's with very smooth tread. My buddy who rides a mtn bike
with slicks says I'm faster than him because of my 23's. I'd LIKE to
think it's me and not the bike.

Is Brandt's work published on the Web somewhere? -paul

I'm sure weight, tire pressure, weight distibution, air drag, and other
factors are at play, too. But yes, tread is bad on a bike tire. Jobst
also found that tread on bike tires are purely cosmetic unless you are
in very slippery terrain. That's why he invented slick tires. If your
tires have very fine tread, it neither helps nor hinders. Most people
want a little tread, because they believe it helps, but Jobst found it
not to be true.

I don't know if it's on the web, but you can find old usenet articles at
http://groups.google.com

And he might be able to answer right here!

Tom