Q. Will I benefit from different tire size or type?

I have 700 x 35 tires on my hybrid bike, and I've recently learned
that I can change the 35 (width?) to a different size, ie. 32, 28 etc.
Question is, do I want to? I ride exclusively on pavement in a city,
so I'd like to maximize tire efficiency for this type of driving.

- First of all, will it work to put different width tires on my
hybrid/city bike, or is there an issue with narrower widths coming off
the rim, etc.?

- Secondly, is there an advantage to using a different tire size if I
can, or should I assume the original 700 x 35 tire size was already
designed ideally for city driving?

- Lastly, I read expert testimonials that said slick tires are best
for pavement riding, cornering, wet driving, traction and have less
rolling resistance, basically because more rubber contacts the road. I
was looking to buy the Michelin Transworld City, but its not a pure
bald slick, it has fairly deep recesses, presumably to siphon off
water (which I read isn't necessary for bike tires, and that this
system doesn't work better than slicks). So my question is, would I be
better off driving in my city with a pure bald slick, such as the
Avocet Road 20, instead of the Michelin Transworld City? Or is it even
better to use DIFFERENT TIRES for the front and back? Any commonly
known disadvantages to going with pure bald untreaded slicks on
pavement, such as premature tire wear, as compared against tires with
a tread?

"Joe Samangitak" wrote in message
om...
I have 700 x 35 tires on my hybrid bike, and I've recently learned
that I can change the 35 (width?) to a different size, ie. 32, 28 etc.
Question is, do I want to? I ride exclusively on pavement in a city,
so I'd like to maximize tire efficiency for this type of driving.

- First of all, will it work to put different width tires on my
hybrid/city bike, or is there an issue with narrower widths coming off
the rim, etc.?

- Secondly, is there an advantage to using a different tire size if I
can, or should I assume the original 700 x 35 tire size was already
designed ideally for city driving?

- Lastly, I read expert testimonials that said slick tires are best
for pavement riding, cornering, wet driving, traction and have less
rolling resistance, basically because more rubber contacts the road. I
was looking to buy the Michelin Transworld City, but its not a pure
bald slick, it has fairly deep recesses, presumably to siphon off
water (which I read isn't necessary for bike tires, and that this
system doesn't work better than slicks). So my question is, would I be
better off driving in my city with a pure bald slick, such as the
Avocet Road 20, instead of the Michelin Transworld City? Or is it even
better to use DIFFERENT TIRES for the front and back? Any commonly
known disadvantages to going with pure bald untreaded slicks on
pavement, such as premature tire wear, as compared against tires with
a tread?

Yes you can switch widths within broad limits ( A 700-47 will probably not
clear your frame and a 700-20 won't last a day on a wide rim). On most fat
700 rims a 32 through 38 are fine. I do not know your rim model so I can't
say what the limits are. If your dealer has a clue s/he should be able to
make a recomendation. Do you want faster? Tougher? A softer ride? The
ability to better corner agressively?

Tread is completely irrelevant on a paved surface.

The Michelin Transworld City is a great urban tire, I like them lots more
than the cheap knobby o.e.m. tires on $300~$500 bikes. They're long-wearing
and smoother riding. That said, the siping is only there to pander to
customers' misunderstandings of tires and treads. Smooth would have been
better and Michelin knows it. They are made in 700-35, 700-32 and 700-28 .
There's theoretically a 700-40 that is perenially on backorder if they ever
made them at all. ( and a nice fat 700-47 that may not be useful to you)

Other popular tires for your bike are Inoue-IRC's Metro 700-38 on the fat
side, Panaracer Pasela 700-35 for a medium tire and the wonderfully fast
IRC Tandem 30 if you are not a heavy or abusive rider and your route is free
of pavement anomalies. Keep the pressure up always but especially if you go
to a skinnier tire.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

"A Muzi" wrote in message ...

Yes you can switch widths within broad limits ( A 700-47 will probably not
clear your frame and a 700-20 won't last a day on a wide rim). On most fat
700 rims a 32 through 38 are fine. I do not know your rim model so I can't
say what the limits are.

32-38 sounds reasonable, I'm not sure its a good idea to push it to
extremes, beyond the original design of 700 x 35.

If your dealer has a clue s/he should be able to
make a recomendation. Do you want faster? Tougher? A softer ride? The
ability to better corner agressively?

I don't care to win any races, but less effort would be nice, because
I'm extremely lazy. Hence the reason I am looking at baldies; less
rolling resistance. The streets the bike will ride on are all paved,
but there are plenty of cracks to deal with, and often have to jump on
or off the sidewalk, so there are bumps to deal with. I don't know
that I need to corner "aggressively", because I'm not an aggresive
rider; but I want to corner -safely-, particularly in wet conditions,
if I get caught in the rain. I do not ever want to crash. It would
help if I simply knew, in general, what the advantages and
disadvantages are between "skinnier" and "fatter" tires.

Tread is completely irrelevant on a paved surface.

The Michelin Transworld City is a great urban tire, I like them lots more
than the cheap knobby o.e.m. tires on $300~$500 bikes. They're long-wearing
and smoother riding.

My original tires were Japanese-made Panaracers (Ridge Line 2). So
they weren't OEM's and they didn't seem cheap, but I'm replacing them
because I recently learned they have no business being on a bike that
is designed to ride exclusively on pavement.

That said, the siping is only there to pander to
customers' misunderstandings of tires and treads. Smooth would have been
better and Michelin knows it.

You see, THIS is why I am thinking of exchanging the Michelin
Transworld City tire that I bought. Because I only learned afterward
that tread siping only caters to ignorant cyclists; which I do not
want to be! If I can get a better tire for no more than the price of
the Transworld City, then I want to get the choice right now.

Other popular tires for your bike are Inoue-IRC's Metro 700-38 on the fat
side, Panaracer Pasela 700-35 for a medium tire and the wonderfully fast
IRC Tandem 30 if you are not a heavy or abusive rider and your route is free
of pavement anomalies. Keep the pressure up always but especially if you go
to a skinnier tire.

The Pasela is not a bald slick, it has some light treads (while the
Transworld City also has a tread, its quite a different surface than
the Pasela). So I'm wondering between the two, which is better and
why? (As for the IRC Metro, although its nearly treadless with little
siping, I only see it listed in mountain bike tire sizes (26 x ?), and
it looks like it will be near impossible for me to get at my local
dealers).

On Sat, 2 Aug 2003 21:34:08 -0500, A Muzi wrote:
of pavement anomalies. Keep the pressure up always but especially if you
go to a skinnier tire.

In fact, the reason to go to a skinnier tire, afaik, is to
be able to use a higher pressure.

I recall a thread that discussed rolling resistance; and
some studies or experiments or something determined that
all things being equal (pressure, tread, compound, bike,
rider, temp, humidity, etc), a wider tire actually has
less rolling resistance. The real-world result, however,
was that narrower tires had lower rolling resistance due
to the higher pressures you could use.

Does anybody else remember that? I don't think it was on
these rec.bicycles newsfroups, but I can't imagine where
it WAS if that's the case.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
--
Rick Onanian

Does it not make sense that the fatter tire will have more rolling
resistance because the contact patch (and thus friction) will be greater
with the fatter tire? If you look at vehicles built for straight-line speed
(other than those where massive power needs to be transmitted to the
ground - definitely NOT bikes) be it soap-box racers to land speed record
assault rocket cars, the tires are hard and skinny to minimize rolling
resistance.

--

- GRL

"It's good to want things."

Steve Barr (philosopher, poet, humorist, chemist,
Visual Basic programmer)
"Rick Onanian" wrote in message
news
On Sat, 2 Aug 2003 21:34:08 -0500, A Muzi wrote:
of pavement anomalies. Keep the pressure up always but especially if you
go to a skinnier tire.

In fact, the reason to go to a skinnier tire, afaik, is to
be able to use a higher pressure.

I recall a thread that discussed rolling resistance; and
some studies or experiments or something determined that
all things being equal (pressure, tread, compound, bike,
rider, temp, humidity, etc), a wider tire actually has
less rolling resistance. The real-world result, however,
was that narrower tires had lower rolling resistance due
to the higher pressures you could use.

Does anybody else remember that? I don't think it was on
these rec.bicycles newsfroups, but I can't imagine where
it WAS if that's the case.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
--
Rick Onanian

"GRL" wrote in message
...
Does it not make sense that the fatter tire will have more rolling
resistance because the contact patch (and thus friction) will be greater
with the fatter tire?


Not necessarily. At a given tire pressure and weight, the contact patch is
*the same size*, no matter how wide (up to a point). Think PSI. Pounds per
sq inch.
A 200lb rider/bike creates a 2 sq in patch for a bike tire pumped to 100
psi. No matter what the width or diameter.

The contact patch will be a different shape for a wider vs skinnier tire.
Wide and short, instead of long and skinny. Less sidewall deformation as the
tire rolls.

This is, of course, making the huge assumption that all other factors are
equal (Tire construction, TPI , pressure, etc).

Width (wind resistance) may overcome the difference in Crr.

If you look at vehicles built for straight-line speed
(other than those where massive power needs to be transmitted to the
ground - definitely NOT bikes) be it soap-box racers to land speed record
assault rocket cars, the tires are hard and skinny to minimize rolling
resistance.

They are also skinny to minimise frontal area/wind resistance. Those types
of vehicles also do not have to worry about wear, traction in varying
conditions, marketing costs, etc.

Several tire rr tests have been done in the recumbent community.
http://www.beezodogsplace.com/Pages/...Resistance.pdf
http://www.legslarry.beerdrinkers.co.uk/tech/GS.htm

Pete

On Thu, 7 Aug 2003 20:08:29 -0400, GRL wrote:

Does it not make sense that the fatter tire will have more rolling
resistance because the contact patch (and thus friction) will be greater
with the fatter tire?

I thought this too, but I now believe that I was incorrect.

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

If you look at vehicles built for straight-line speed
(other than those where massive power needs to be transmitted to the
ground - definitely NOT bikes) be it soap-box racers to land speed record
assault rocket cars, the tires are hard and skinny to minimize rolling
resistance.

The narrow tires are more aerodynamic and can take higher pressures.

--
Rick Onanian

On 2 Aug 2003 19:19:02 -0700, (Joe Samangitak)
may have said:

- First of all, will it work to put different width tires on my
hybrid/city bike, or is there an issue with narrower widths coming off
the rim, etc.?

Not knowing the rim width, it's hard to say what range of sizes will
work well. You may be able to go down a few sizes, but do you want
to? Less rubber between the road and the rim can yield a harsher ride
and an increased probability of punctures.

- Secondly, is there an advantage to using a different tire size if I
can, or should I assume the original 700 x 35 tire size was already
designed ideally for city driving?

Make no unwarranted assumptions; the size could have been chosen for
any number of reasons that may or may not be relevant to you. All
that you can likely assume is that 700x35 is a safe size to use on
your rims.

- Lastly, I read expert testimonials that said slick tires are best
for pavement riding, cornering, wet driving, traction and have less
rolling resistance, basically because more rubber contacts the road.

For bicycles, that's pretty much true. Unlike motor vehicle tires,
where the tread is essential to prevent aquaplaning due to the large
size of the contact patch, a 700x35 bike tire has a small enough patch
(and is typically used at a low enough speed) that the aquaplaning
issue simply doesn't apply. While there are some who will state that
a treaded tire will not slip as easily on a damp polished concrete
surface (which is inherently treacherous territory), it's been my
experience that such surfaces are only likely to be found indoors or
in locations where you're more likely to be walking than riding. A
car's tread wouldn't prevent a slip on such a surface, so a bike's
tread isn't likely to help either. As such, the only remaining reason
to favor a siped or treaded tire over a fully slick one is the fact
that you won't be caught by surprise when it wears out; the
disappearing sipes or tread make it really obvious without even having
to pay close attention. I would not consider minor siping or
patterning to be a drawback that disqualified a tire that was being
bought for commuter use, since the sipes or patternings most likely
would not reduce the tire's useful life by a tremendous amount.



--
My email address is antispammed;
pull WEEDS if replying via e-mail.
Yes, I have a killfile. If I don't respond to something,
it's also possible that I'm busy.

Joe Samangitak wrote:
- Lastly, I read expert testimonials that said slick tires are best
for pavement riding, cornering, wet driving, traction and have less
rolling resistance, basically because more rubber contacts the road. I
was looking to buy the Michelin Transworld City, but its not a pure
bald slick, it has fairly deep recesses, presumably to siphon off
water (which I read isn't necessary for bike tires, and that this
system doesn't work better than slicks). So my question is, would I be
better off driving in my city with a pure bald slick, such as the
Avocet Road 20, instead of the Michelin Transworld City?

Possibly but it doesn't mean siped tyres should be avoided, because they
may happen to be generally excellent tyres still with plenty of grip (more
grip than more heavily treaded tyres on road). There aren't too many
totally slick tyres on the market so it's unwise to limit yourself just to
them.

Or is it even
better to use DIFFERENT TIRES for the front and back?

Front tyre takes less weight and gets an easier life so it can be
different - different width, different tread, certainly different
pressure. Grip is more of an important factor for front tyre as well.

Any commonly
known disadvantages to going with pure bald untreaded slicks on
pavement, such as premature tire wear, as compared against tires with
a tread?

Treaded tyres tend to have a deeper layer of rubber so are more puncture
resistant and last longer. If this is a major concern, you could use a
tyre like this at the rear with a lighter, slicker tyre on the front.

~PB

On 2 Aug 2003 19:19:02 -0700, (Joe Samangitak)
wrote:

I have 700 x 35 tires on my hybrid bike, and I've recently learned
that I can change the 35 (width?) to a different size, ie. 32, 28 etc.
Question is, do I want to? I ride exclusively on pavement in a city,
so I'd like to maximize tire efficiency for this type of driving.

- First of all, will it work to put different width tires on my
hybrid/city bike, or is there an issue with narrower widths coming off
the rim, etc.?


Yes, you can put thinner width tires on.

- Secondly, is there an advantage to using a different tire size if I
can, or should I assume the original 700 x 35 tire size was already
designed ideally for city driving?

The 35mm was chosen for its aesthetic appeal to the target market for
the bicycle. I'd imagine that most hybrid buyers will put more value
on comfort and the feeling of safety a bigger tire gives than on speed
and efficiency.

There are advantages and disadvantages to narrower tires.

Since they are smaller and often have less rubber than wider tires,
they weigh less and are easier to accelerate. My city riding has a lot
of stops and slowdowns, so it makes a difference for me.

A smaller contact patch means less friction, so they are faster, but
my gut says that this is actually a relatively small difference.

Higher pressure, so less time and energy spent over bumps, etc..
moving the tire itself rather than the whole bike.

Higher pressure and thinner rubber can mean more flats. And more road
bumps transmitted into your body rather than absorbed by the tire.

Road cracks and potholes become much more important. Something that I
can ignore on wide tires can catch a skinny tire and send me down if I
don't pay attention.

For me, different tires and bikes lead to different riding experiences
in a city. A narrow tire requires more attention to the road, I seem
to go faster and so have to pay more attention to traffic, and going
faster can be both stressful and fun. A fatter tire lets me be more
relaxed about the road condition, is less jarring, and lets me jump
curbs and do other things that I wouldn't try on narrow tires.

That's the trade-off I see- speed, precision, and the need to maintain
focus on the road versus comfort, slop, and the ability to not be too
concerned with the road. Each of us finds our own balance point.

I would suggest finding a 28mm tire that is lighter than your present
one and trying it out. Maybe your bike shop has a bike similar to
yours with tires this size, and you can run it around the block to see
how it feels?

Don't forget how important tire pressure is, also. The same tire can
take on very different characteristics at different pressures. I have
some Continental Travel Contacts on a mountain bike, which are 1.75
inches wide. I can use than at 45 lbs or at 80 lbs, and it is close to
changing tires when I change the pressure. If you are running your
present tires at the lower end of their pressure range, go to the top
end to get a taste of some of the changes skinnier tires will make.
Even five or ten pounds can make a huge difference in how a tire
rides.

- Lastly, I read expert testimonials that said slick tires are best
for pavement riding, cornering, wet driving, traction and have less
rolling resistance, basically because more rubber contacts the road. I
was looking to buy the Michelin Transworld City, but its not a pure
bald slick, it has fairly deep recesses, presumably to siphon off
water (which I read isn't necessary for bike tires, and that this
system doesn't work better than slicks). So my question is, would I be
better off driving in my city with a pure bald slick, such as the
Avocet Road 20, instead of the Michelin Transworld City? Or is it even
better to use DIFFERENT TIRES for the front and back? Any commonly
known disadvantages to going with pure bald untreaded slicks on
pavement, such as premature tire wear, as compared against tires with
a tread?

20mm tires in a city seems extreme. I ride 23mm on one bike and I
think that the next set will be 25mm. 23 just requires more attention
and care than I feel like giving all the time. Then again, I've ridden
23mms in a city for years and keep buying them. 32mm on another bike
was just a bit too heavy and wide for my needs and taste.

Tire life depends on the thickness and quality of the rubber. Tread
per se has nothing to do with it. No tread pattern or a minimal
siping is what I look for. About all you gain from heavy treads is a
funny road buzz and energy going into moving the tire knobs around
rather than moving you forward. But as someone already said, marketing
drives a lot of the tire design issues, so I wouldn't let minimal
treads stop you from buying a tire outright. City riding is not about
the absolute highest level of efficiency. What is very critical to a
racer is one small factor among many for non-competetive city riding.