tire sizing gripe

As someone who helps run a community non-profit bike shop, one thing
that bugs me are uninformed dopes that want to buy a fixed-gear bike
without actually knowing what one is.

The other is tire sizing. We have enough trouble dealing with the
variety of the past, with the various sizes of 26", 24", etc. And we
silly Canadians have been calling ISO 622 (aka 700C) as 28" for many
decades, even though they are smaller than 27s (ISO 630). (To me the
real 28" is the old roadster 28 x 1 1/2 ISO 635.)

Recently it took me a while to find a pair of tires in 24 x 1 1/4 (ISO
547), and have also had fun trying to read worn-out sidewalls to find
out if a 26" is 590 or 597 (five of them were 597s!). But I can cope
with that, as most either have the ISO or at least the E. or S.
designation so I can refer to Sheldon's chart.

Now there's this dopey business of calling mtn. bikes fitted with 700C
as "29er". Probably once again due to measuring the inflated tire and
of course not the actual rim diameter. And even newer apparently is
calling 650B as 27.5! Crap, at ISO 584 it's a a fair bit smaller than
a 27" / 630, so what's with this? Is it the marketing geeks, or the
riders themselves?

Whoever it is, please stop this silliness, or we may have to summon
the Ghost of Sheldon to whump you upside the head (if it is so
inclined). Even though I think the 650B "revival" is a bit precious,
I don't care how many sizes are available as long as they are properly
identified.

Mark (griping for fun and no profit)

Mark wrote:

As someone who helps run a community non-profit bike shop, one thing
that bugs me are uninformed dopes that want to buy a fixed-gear bike
without actually knowing what one is.

Sell them coaster-braked road bikes. They'll like them better, they
might not get killed, and you'll sleep soundly at night.

Now there's this dopey business of calling mtn. bikes fitted with 700C
as "29er". *Probably once again due to measuring the inflated tire and
of course not the actual rim diameter. *

ISO 622 is ubiquitous. And most 700c bikes are *not* 29ers. It's
fair to have a simple term for them, because a 29er tire will not fit
into a non-29er frame, even if it will fit on a non-29er rim.

And even newer apparently is
calling 650B as 27.5! *Crap, at ISO 584 it's a a fair bit smaller than
a 27" / 630, so what's with this? *Is it the marketing geeks, or the
riders themselves?

ISO 584 is for looz0rz. There is no excuse for it. 559 and 622 are
the valid sizes, and for those who must have offbeat 'tween-sized
rolling stock, ISO 590 has been breathing continuously all this time.
584 is a practical joke, an IQ test, a self-punishing mistake.

Chalo

On 20 Sep, 05:53, Chalo wrote:
Mark wrote:

As someone who helps run a community non-profit bike shop, one thing
that bugs me are uninformed dopes that want to buy a fixed-gear bike
without actually knowing what one is.

Sell them coaster-braked road bikes. *They'll like them better, they
might not get killed, and you'll sleep soundly at night.

Now there's this dopey business of calling mtn. bikes fitted with 700C
as "29er". *Probably once again due to measuring the inflated tire and
of course not the actual rim diameter. *

ISO 622 is ubiquitous. *And most 700c bikes are *not* 29ers. *It's
fair to have a simple term for them, because a 29er tire will not fit
into a non-29er frame, even if it will fit on a non-29er rim.

At what tyre size does a 700c wheeled machine magically become a
29er? I would hazard a guess that it is over a 35mm tyre. 35mm being
the limit set by the uci for competetive machines.

Chalo Colina wrote:
[...]
ISO 584 is for looz0rz. There is no excuse for it. 559 and 622 are
the valid sizes, and for those who must have offbeat 'tween-sized
rolling stock, ISO 590 has been breathing continuously all this time.
584 is a practical joke, an IQ test, a self-punishing mistake.

No, the valid sizes are ISO 305-mm and ISO 406-mm. What is a joke is the
combined existence of ISO 349-mm, 355-mm and 369-mm.

--
Tom Sherman - 42.435731,-83.985007

On 20 Sep, 08:07, Tom Sherman °_°
wrote:
Chalo Colina wrote:
[...]
ISO 584 is for looz0rz. *There is no excuse for it. *559 and 622 are
the valid sizes, and for those who must have offbeat 'tween-sized
rolling stock, ISO 590 has been breathing continuously all this time.
584 is a practical joke, an IQ test, a self-punishing mistake.

No, the valid sizes are ISO 305-mm and ISO 406-mm. What is a joke is the
combined existence of ISO 349-mm, 355-mm and 369-mm.


Standardizing tyre sizes to an 8" bead increment using letter codes
would be nice starting at 32" bead length for the smallest A size,
40" B
48" C
56" D
64" E
72" F
80" G a 622 DIA bead equivalent
88" H

The width of the tyre to represent the casing size bead to bead a
letter related to each 1/8" over 2" so a 3" bead to bead dimension
would be a G width.

So a 622 x 23 wired tyre in todays naming would be replaced by a GG
bicycle tyre. All racing bicycle frames must be capable of taking a J
cross section.

someone wrote:

Chalo wrote:

Mark wrote:

Now there's this dopey business of calling mtn. bikes fitted with 700C
as "29er". *Probably once again due to measuring the inflated tire and
of course not the actual rim diameter. *

ISO 622 is ubiquitous. *And most 700c bikes are *not* 29ers. *It's
fair to have a simple term for them, because a 29er tire will not fit
into a non-29er frame, even if it will fit on a non-29er rim.

At what tyre size does a 700c wheeled machine magically become a
29er? *I would hazard a guess that it is over a 35mm tyre. *35mm being
the limit set by the uci for competetive machines.

The selection of 700c tires available before 29" MTBs stopped at a
nominal 700x47 (which were usually much narrower if you bothered to
measure them). That seems like as good a place as any for me to make
a distinction. Thus, 48-622 and up are "29 inch" tires.

I like 60-622 tires, which measure closer to an actual 30" when
mounted on rims of normal width.

Chalo

Standardizing tyre sizes to an 8" bead increment using letter codes
would be nice starting at 32" bead length for the smallest A size,
40" B
48" C
56" D
64" E
72" F
80" G a 622 DIA bead equivalent
88" H

You must be speaking of bead *circumference*, yes?

I think if the industry would standardize on existing sizes and not introduce
any more that would be a huge gain! ;-)

On Sep 20, 1:46*pm, RonSonic wrote:
On Sun, 20 Sep 2009 01:33:38 -0700 (PDT), someone wrote:
On 20 Sep, 08:07, Tom Sherman °_°
wrote:
Chalo Colina wrote:
[...]
ISO 584 is for looz0rz. *There is no excuse for it. *559 and 622 are
the valid sizes, and for those who must have offbeat 'tween-sized
rolling stock, ISO 590 has been breathing continuously all this time..
584 is a practical joke, an IQ test, a self-punishing mistake.

No, the valid sizes are ISO 305-mm and ISO 406-mm. What is a joke is the
combined existence of ISO 349-mm, 355-mm and 369-mm.

Standardizing tyre sizes to an 8" bead increment using letter codes
would be nice starting at 32" bead length for the smallest A size,
40" B
48" C
56" D
64" E
72" F
80" G a 622 DIA bead equivalent
88" H

The width of the tyre to represent the casing size bead to bead a
letter related to each 1/8" over 2" so a 3" bead to bead dimension
would be a G width.

So a 622 x 23 wired tyre in todays naming would be replaced by a GG
bicycle tyre. *All racing bicycle frames must be capable of taking a J
cross section.

I've just read that twice and still have no idea what your measurement system
means. So not just no, but hell no. Okay, now three times.

I can remember most of the archaic systems, and easily grasp the ISO. So, just
hell no.


My _new_ system is based on loaded-tire-roll-out in
cubits. It uses roman numerals for everything smaller
than 0.80, hellenic letters (including the obsolete digamma)
from everything from 0.81-2.09 and just the number to a
random number of significant digits for everything 2.10000
and larger. The rim size will be indicated by the first lines
of cantos from the Faerie Queene rendered in palindromatic
latin.

My _new_ system is based on loaded-tire-roll-out in
cubits. It uses roman numerals for everything smaller
than 0.80, hellenic letters (including the obsolete digamma)
from everything from 0.81-2.09 and just the number to a
random number of significant digits for everything 2.10000
and larger. The rim size will be indicated by the first lines
of cantos from the Faerie Queene rendered in palindromatic
latin.

Do they come in granite?

On Sep 20, 8:49*pm, Norman wrote:
On Sep 20, 1:46*pm, RonSonic wrote:





On Sun, 20 Sep 2009 01:33:38 -0700 (PDT), someone wrote:
On 20 Sep, 08:07, Tom Sherman °_°
wrote:
Chalo Colina wrote:
[...]
ISO 584 is for looz0rz. *There is no excuse for it. *559 and 622 are
the valid sizes, and for those who must have offbeat 'tween-sized
rolling stock, ISO 590 has been breathing continuously all this time.
584 is a practical joke, an IQ test, a self-punishing mistake.

No, the valid sizes are ISO 305-mm and ISO 406-mm. What is a joke is the
combined existence of ISO 349-mm, 355-mm and 369-mm.

Standardizing tyre sizes to an 8" bead increment using letter codes
would be nice starting at 32" bead length for the smallest A size,
40" B
48" C
56" D
64" E
72" F
80" G a 622 DIA bead equivalent
88" H

The width of the tyre to represent the casing size bead to bead a
letter related to each 1/8" over 2" so a 3" bead to bead dimension
would be a G width.

So a 622 x 23 wired tyre in todays naming would be replaced by a GG
bicycle tyre. *All racing bicycle frames must be capable of taking a J
cross section.

I've just read that twice and still have no idea what your measurement system
means. So not just no, but hell no. Okay, now three times.

I can remember most of the archaic systems, and easily grasp the ISO. So, just
hell no.

My _new_ system is based on loaded-tire-roll-out in
cubits. *It uses roman numerals for everything smaller
than 0.80, hellenic letters (including the obsolete digamma)
from everything from 0.81-2.09 and just the number to a
random number of significant digits for everything 2.10000
and larger. *The rim size will be indicated by the first lines
of cantos from the Faerie Queene rendered in palindromatic
latin.

Several forward-looking mailorder degree factories are already
considering offering PhDs in deciphering your system. It is a stroke
of genius, Norman, that will give surplus LBSs a new lease on life. --
Andre Jute