Tire size on a Mavic Open
James Thomson
> What is the largest size tire that can fit on a Mavic
> Open Pro rim?
I've had a 37mm (Panaracer CTX 737) on mine without problems at
pressures as high as 90psi (and as low as 30psi). Obviously, the
broader the tyre you choose, the greater the stresses on the rim
walls, and I can't comment on the long term durability of such an
extreme combination.
James Thomson
Mike Jacoubowsky
#1: Lots of pressure in a wide tire will overload the design of the
sidewalls, possibly causing them to fail prematurely. This might not happen
soon, but over time, sidewalls become thinner as the brakes wear away the
surface. A wide tire at relatively lower pressures (say 70psi) probably
isn't much of a problem, but if you're going to run a wide tire at 90psi
etc....could be an issue.
#2: You may not have much clearance for a really wide tire on a bike that
came with narrow rims. Check the fork crown (both the sides and top, since
a wide tire is also "taller" than a narrow one) and the chainstays.
--Mike-- Chain Reaction Bicycles
http://www.ChainReactionBicycles.com
"Gocycle" <Goc...@webtv.net> wrote in message
news:21250-39...@storefull-618.iap.bryant.webtv.net...
> What is the largest size tire that can fit on a Mavic Open Pro rim?
>
> Thanks to all
> Luigi
>
>
>
>
> }}}}}GoCycle}}}}}
>
Gocycle
Don Vescio
response a little more? A bigger tire would have more volume of air, but
isn't pressure just pressure? In other words, why would 90psi in a 35c tire
be any different than 90psi in a 23c tire.
Kinda of curious, as I've been wondering about this in regards to 'cross
clinchers.
Don
"Mike Jacoubowsky" <Mik...@ix.netcom.com> wrote in message
news:B08x5.9853$oc3.6...@news.flash.net...
> You can run a fairly wide tire, but there are two constraints:
>
> #1: Lots of pressure in a wide tire will overload the design of the
> sidewalls, possibly causing them to fail prematurely. This might not
happen
> soon, but over time, sidewalls become thinner as the brakes wear away the
> surface. A wide tire at relatively lower pressures (say 70psi) probably
> isn't much of a problem, but if you're going to run a wide tire at 90psi
> etc....could be an issue.
>
> #2: You may not have much clearance for a really wide tire on a bike that
> came with narrow rims. Check the fork crown (both the sides and top,
since
> a wide tire is also "taller" than a narrow one) and the chainstays.
>
> --Mike-- Chain Reaction Bicycles
> http://www.ChainReactionBicycles.com
>
>
> "Gocycle" <Goc...@webtv.net> wrote in message
> news:21250-39...@storefull-618.iap.bryant.webtv.net...
A Muzi
least.
Gocycle wrote:
> What is the largest size tire that can fit on a Mavic Open Pro rim?
>
> Thanks to all
> Luigi
>
> }}}}}GoCycle}}}}}
--
Yellow Jersey, Ltd
http://www.yellowjersey.org
http://www.execpc.com/yellowje
Open every day since 1 April, 1971
James Thomson
> > of the sidewalls, possibly causing them to fail prematurely.
> > This might not happen soon, but over time, sidewalls become
> > thinner as the brakes wear away the surface. A wide tire at
> > relatively lower pressures (say 70psi) probably isn't much of
> > a problem, but if you're going to run a wide tire at 90psi etc...
Don Vescio <don.v...@digitalinspirations.com> wrote:
> I'm not challenging what you're saying [above], but could you
> explain you response a little more? A bigger tire would have
> more volume of air, but isn't pressure just pressure? In other
> words, why would 90psi in a 35c tire be any different than
> 90psi in a 23c tire.
Equal pressure just means that the force per unit area exerted by the
air against the inside of the tyre is the same. The total area
increases roughly in proportion to the width of the tyre, so the total
force acting on a given length of rim wall also increases in the same
proportion, as well as in proportion to the pressure in the tyre.
James Thomson
Don Vescio
Don
"James Thomson" <Sna...@jcet.freeserve.co.uk> wrote in message
news:8q3gun$mai$1...@news6.svr.pol.co.uk...
A Muzi
Mike Jacoubowsky wrote:
> -snip-
I'm not necessarily disagreeing with you, just wondering why 100psi in a 23mm
tire would be different from 100psi in a 43mm tire. Isn't pneumatic pressure
spread evenly over the area of the rim's surface at a constant pressure?
> Lots of pressure in a wide tire will overload the design of the
> sidewalls, possibly causing them to fail prematurely.
--
Sheldon Brown
> > > What is the largest size tire that can fit on a Mavic Open Pro rim?
Mike Jacoubowsky answered:
> > You can run a fairly wide tire, but there are two constraints:
> >
> > #1: Lots of pressure in a wide tire will overload the design of the
> > sidewalls, possibly causing them to fail prematurely. This might not
> happen
> > soon, but over time, sidewalls become thinner as the brakes wear away the
> > surface. A wide tire at relatively lower pressures (say 70psi) probably
> > isn't much of a problem, but if you're going to run a wide tire at 90psi
> > etc....could be an issue.
> >
> > #2: You may not have much clearance for a really wide tire on a bike that
> > came with narrow rims.
Don Vescio wrote:
>
> I'm not challenging what you're saying, but could you explain your
> response a little more? A bigger tire would have more volume of air, but
> isn't pressure just pressure? In other words, why would 90psi in a 35c tire
> be any different than 90psi in a 23c tire.
The inflation creates a tensile (pulling) stress on the tire. If the
tire is the same width as the rim, this pull, at the edge of the tire,
is straight up away from the rim, and the stress is taken up pretty much
entirely by the wire (or Kevlar) bead.
If the tire bulges way out past the rim, because of being much fatter,
the tensile load is acting in a direction to pull the outside edges of
the rim outward. This sort of splaying out is the usual failure mode
for rims that have worn out as a result of brake wear.
> Kinda of curious, as I've been wondering about this in regards to 'cross
> clinchers.
The fact is that there is no reason to inflate such a wide tire to such
high pressure. Indeed, the primary _purpose_ of wide tires is to allow
you to run them at _lower_ pressures without running into problems with
pinch cuts. A 35 mm tire at 90 psi (6 bar) would be grossly
overinflated even for tandem use, but might be appropriate for a triplet.
Unfortunately, if you mount a 35 mm tire on a skinny rim like this, you
can't really deflate it to a good off-road riding pressure without
risking having the tire "wallow" sideways in cornering. This is a
common problem with MTBs that frequently have rims that are really too
narrow for their tires, in the name of weight saving.
That said, I do run 32 mm Ritchey Tom Slicks on similar rims on a couple
of my bikes, generally 70 psi front, 80 rear. The Ritcheys are _actual_
32 mm tires, and many tires _marked_ 35 are actually narrower.
Sheldon "http://sheldonbrown.com/tires.html" Brown
+-----------------------------------+
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| who have no style of their own. |
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+-----------------------------------+
Harris Cyclery, West Newton, Massachusetts
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Damon Rinard
geometry.
For any given tire pressure, as the minor radius of the tire, r,
increases, the tire casing's tensile force, pr, becomes both larger in
magnitude and more nearly horizontal. As a consequence, the horizontal
component of this force, F(h), grows. This is the horizontal force (per
unit length around the rim) that tends to pull the rim side walls
apart. Thus larger tires, if inflated to the same pressure as norrower
ones, cause greatly increased bending force on the rim side wall.
In article <SX8x5.3994$T6.1...@typhoon2.ba-dsg.net>,
"Don Vescio" <don.v...@digitalinspirations.com> wrote:
> I'm not challenging what you're saying below, but could you explain
your
> response a little more? A bigger tire would have more volume of air,
but
> isn't pressure just pressure? In other words, why would 90psi in a
35c tire
> be any different than 90psi in a 23c tire.
>
> Kinda of curious, as I've been wondering about this in regards
to 'cross
> clinchers.
>
> Don
>
> "Mike Jacoubowsky" <Mik...@ix.netcom.com> wrote in message
> news:B08x5.9853$oc3.6...@news.flash.net...
> > You can run a fairly wide tire, but there are two constraints:
> >
> > #1: Lots of pressure in a wide tire will overload the design of the
> > sidewalls, possibly causing them to fail prematurely. This might
not
> happen
> > soon, but over time, sidewalls become thinner as the brakes wear
away the
> > surface. A wide tire at relatively lower pressures (say 70psi)
probably
> > isn't much of a problem, but if you're going to run a wide tire at
90psi
> > etc....could be an issue.
> >
> > #2: You may not have much clearance for a really wide tire on a
bike that
> > came with narrow rims. Check the fork crown (both the sides and
top,
> since
> > a wide tire is also "taller" than a narrow one) and the chainstays.
> >
> > --Mike-- Chain Reaction Bicycles
> > http://www.ChainReactionBicycles.com
> >
> >
> > "Gocycle" <Goc...@webtv.net> wrote in message
> > news:21250-39...@storefull-618.iap.bryant.webtv.net...
> > > What is the largest size tire that can fit on a Mavic Open Pro
rim?
> > >
> > > Thanks to all
> > > Luigi
> > >
> > >
> > >
> > >
> > > }}}}}GoCycle}}}}}
> > >
> >
> >
>
>
--
Damon Rinard: dri...@yahoo.com
Bicycle Tech Site:
http://www.damonrinard.com/
Sent via Deja.com http://www.deja.com/
Before you buy.
Peter Cole
Gocycle
stress to the Mavic Open Pro?
Luigi
}}}}}GoCycle}}}}}
Gene Tolli
Cyclocross Sprint tire, (laughably labeled as a 700x30 but really a 34)
on a Velocity Aerohead rim. Would a wider rim (22-24), possibly slightly
heavier be a smarter choice for the rear of a cross bike?
I use low pressure, anywhere from 40-60 psi, so I guess my question
isn't directly related to the original question.
--
Regards,
Gene Tolli
form...@mailbag.com