After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?

On Thu, 18 Oct 2018 11:36:28 +0100, "Jim GM4DHJ ..."
wrote:

After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?

It's the bead that normally determines how well a tyre fits a rim and
as they are normally kevlar or steel I find it had to see how it could
have 'grown'?

Cheers, T i m

On 18/10/2018 11:36, Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?


When the inner tube is inflated, doesn't it push the bead out into the
correct location on the rim?

Nick

"Nick Odell" wrote in message
news
On 18/10/2018 11:36, Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


When the inner tube is inflated, doesn't it push the bead out into the
correct location on the rim?

Nick

no that was the strange thing...it was far to large a diameter to even come
near the rim with the tube inflated.....never mind it is in the bin
now..........

"Nick Odell" wrote in message
news
On 18/10/2018 11:36, Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


When the inner tube is inflated, doesn't it push the bead out into the
correct location on the rim?

Nick

no far too big a dia..

"Tim Streater" wrote in message
.. .
In article , Jim GM4DHJ ...
wrote:

"Nick Odell" wrote in message
news
On 18/10/2018 11:36, Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?

When the inner tube is inflated, doesn't it push the bead out into the
correct location on the rim?

no that was the strange thing...it was far to large a diameter to even
come near the rim with the tube inflated.....never mind it is in the bin
now..........

Did you not join the dots? Or perhaps it was caused by you tearing
along the dotted line.

.........that will be it...tee hee

"Jim GM4DHJ ..." wrote in message
...
After a puncture and a ruined tyre I tried to put back on an old 28 inch bike tyre that
WAS on the bike years ago only to find its diameter was now far to big to fit the
rim....is this normal ?


It may have been on that bike are you sure was it on the same (sized)
wheel ? Given its possible to fit different size wheels on the same
frame by way of replacements, etc.

Non folding bike tyres have a continuous wire mouded into the bead
which snaps over the rim. While its conceivable that the joint in
this wire may have failed that wouldn't explain why the rubber has
stretched as well


michael adams

....

"michael adams" wrote in message
o.uk...

"Jim GM4DHJ ..." wrote in message
...
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now far to big to fit the rim....is this normal ?


It may have been on that bike are you sure was it on the same (sized)
wheel ? Given its possible to fit different size wheels on the same
frame by way of replacements, etc.

Non folding bike tyres have a continuous wire mouded into the bead
which snaps over the rim. While its conceivable that the joint in
this wire may have failed that wouldn't explain why the rubber has
stretched as well


michael adams

yip 28 inch

Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have simply
mis-remembered which bike or wheel the tyre came off. My money is on the
latter.

Ive kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time in the
past? What size did the ruined tyre claim to be in the sidewall? What was
the figure printed on the sidewall of the €œstretched€� tyre?

Tim

--
Please don't feed the trolls

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have simply
mis-remembered which bike or wheel the tyre came off. My money is on the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time in
the
past? What size did the ruined tyre claim to be in the sidewall? What was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have simply
mis-remembered which bike or wheel the tyre came off. My money is on the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time in
the
past? What size did the ruined tyre claim to be in the sidewall? What was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

But are the rims 28inch?

"Richard" wrote in message
news
On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have simply
mis-remembered which bike or wheel the tyre came off. My money is on
the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time in
the
past? What size did the ruined tyre claim to be in the sidewall? What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no idea
what happened

"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news
On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have simply
mis-remembered which bike or wheel the tyre came off. My money is on
the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time in
the
past? What size did the ruined tyre claim to be in the sidewall? What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then
--
Chris French

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news
On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is on
the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time
in
the
past? What size did the ruined tyre claim to be in the sidewall? What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...

"Chris French" wrote in message
...
There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then


One thing about ISO sizes bewilders me: why do they specify the height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to do it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter (ie of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in inches
(for US) - not some half-arsed mixture of the two.

Yes rubber can be like that. I have a knob on a radio here and the rubber
outer is now so big I have to put tape underneath it to stop it falling off!
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Jim GM4DHJ ..." wrote in message
...
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?

Well they do, or at least used to when I could use a bike.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"T i m" wrote in message
...
On Thu, 18 Oct 2018 11:36:28 +0100, "Jim GM4DHJ ..."
wrote:

After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was now
far to big to fit the rim....is this normal ?

It's the bead that normally determines how well a tyre fits a rim and
as they are normally kevlar or steel I find it had to see how it could
have 'grown'?

Cheers, T i m

Beads on older tyres were not so sophisticated. It was often just a denser
rubber.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Jim GM4DHJ ..." wrote in message
...

"Nick Odell" wrote in message
news
On 18/10/2018 11:36, Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28 inch
bike tyre that WAS on the bike years ago only to find its diameter was
now
far to big to fit the rim....is this normal ?


When the inner tube is inflated, doesn't it push the bead out into the
correct location on the rim?

Nick

no that was the strange thing...it was far to large a diameter to even
come near the rim with the tube inflated.....never mind it is in the bin
now..........

On Thu, 18 Oct 2018 18:00:12 +0100, "Brian Gaff"
wrote:

Well they do, or at least used to when I could use a bike.

Can't say it's something I've ever experienced over 50 years and many
bikes (currently 10 solos between us, a cycle trailer and tandem).

Maybe I've never had a bike (or tyre) that might be likely to suffer
such?

Presumably you could have a tyre come off the rim when is use then
(after being on there with no issues for some time)?

Cheers, T i m

On Thu, 18 Oct 2018 17:45:14 +0100, "NY" wrote:

"Chris French" wrote in message
...
There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then


One thing about ISO sizes bewilders me: why do they specify the height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to do it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter (ie of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in inches
(for US) - not some half-arsed mixture of the two.

+1

Cheers, T i m

Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is on
the
latter.

I've kept many old bike tyres for years and in my experience, the bead
*never* changes in size. Have you had new wheels put on at any time
in
the
past? What size did the ruined tyre claim to be in the sidewall? What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike ....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


Thats nearer 26€� than 28€�. As I said, its most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links to
photos of what is *actually* printed on the sidewalks of your ruined and
€œstretched€� tyre please. Tyres just Do Not Stretch in storage.

Tim

--
Please don't feed the trolls

T i m wrote:
On Thu, 18 Oct 2018 18:00:12 +0100, "Brian Gaff"
wrote:

Well they do, or at least used to when I could use a bike.

Can't say it's something I've ever experienced over 50 years and many
bikes (currently 10 solos between us, a cycle trailer and tandem).


Nor me. It just doesnt happen. The stored tyre must have been for a
different wheel.

Tim


--
Please don't feed the trolls st have been for a different wheel.

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is
on
the
latter.

I've kept many old bike tyres for years and in my experience, the
bead
*never* changes in size. Have you had new wheels put on at any time
in
the
past? What size did the ruined tyre claim to be in the sidewall?
What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike
....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


That's nearer 26" than 28". As I said, it's most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links to
photos of what is *actually* printed on the sidewalks of your ruined and
"stretched" tyre please. Tyres just Do Not Stretch in storage.


OK OK I will dig it out of the bin tomorrow ......

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old 28
inch
bike tyre that WAS on the bike years ago only to find its diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is
on
the
latter.

I've kept many old bike tyres for years and in my experience, the
bead
*never* changes in size. Have you had new wheels put on at any time
in
the
past? What size did the ruined tyre claim to be in the sidewall?
What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike
....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


That's nearer 26" than 28". As I said, it's most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links to
photos of what is *actually* printed on the sidewalks of your ruined and
"stretched" tyre please. Tyres just Do Not Stretch in storage.

Tim

OK just been out the back door the one that is too large to fit is on the
bin and the one that does fit is on the bikeobviously...haven't looked at
the sizes myself but I will stand by your findings...thanks

https://www.photobox.co.uk/my/album?album_id=5416389667

"Jim GM4DHJ ..." wrote in message
news

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old
28
inch
bike tyre that WAS on the bike years ago only to find its diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is
on
the
latter.

I've kept many old bike tyres for years and in my experience, the
bead
*never* changes in size. Have you had new wheels put on at any
time
in
the
past? What size did the ruined tyre claim to be in the sidewall?
What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike
....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


That's nearer 26" than 28". As I said, it's most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links
to
photos of what is *actually* printed on the sidewalks of your ruined and
"stretched" tyre please. Tyres just Do Not Stretch in storage.

Tim

OK just been out the back door the one that is too large to fit is on the
bin and the one that does fit is on the bikeobviously...haven't looked at
the sizes myself but I will stand by your findings...thanks

https://www.photobox.co.uk/my/album?album_id=5416389667

they look the same size to me ......????

"Jim GM4DHJ ..." wrote in message
...

"Jim GM4DHJ ..." wrote in message
news

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old
28
inch
bike tyre that WAS on the bike years ago only to find its
diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money is
on
the
latter.

I've kept many old bike tyres for years and in my experience, the
bead
*never* changes in size. Have you had new wheels put on at any
time
in
the
past? What size did the ruined tyre claim to be in the sidewall?
What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike
....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put
it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


That's nearer 26" than 28". As I said, it's most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links
to
photos of what is *actually* printed on the sidewalks of your ruined and
"stretched" tyre please. Tyres just Do Not Stretch in storage.

Tim

OK just been out the back door the one that is too large to fit is on the
bin and the one that does fit is on the bikeobviously...haven't looked at
the sizes myself but I will stand by your findings...thanks

https://www.photobox.co.uk/my/album?album_id=5416389667

they look the same size to me ......????

the destroyed one at the bottom of th bin covered in cat litter which I am
not going to remove from the bin reads 37-622 (28x 15/8x 13/8) ....

On 18/10/2018 17:45, NY wrote:
"Chris French" wrote in message
...
There are two different '28 inch ' tyre sizes though,Â* those with
a bead diameter of 635mm, otherwiseÂ* known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then


One thing about ISO sizes bewilders me: why do they specify the height
of the tyre (OD - ID) as a percentage of the width? Seems an odd way to
do it. Surely the three measurements that need to be specified
explicitly a inside diameter (ie diameter of wheel and of bead),
outside diameter (ie of tread) and width. And preferably specify all
three in the same bloody units - either all in mm for Europe (and
*maybe* UK) or else all in inches (for US) - not some half-arsed mixture
of the two.

Similar to car tyres then? 205/55R16 has a sidewall height of 55% of
205mm on a 16" rim. If the second figure is missing, such as 185R13,
then the height is 80% of the first figure.

SteveW

"Jim GM4DHJ ..." wrote in message
...

"Jim GM4DHJ ..." wrote in message
...

"Jim GM4DHJ ..." wrote in message
news

"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:

"Chris French" wrote in message
...
"Jim GM4DHJ ..." Wrote in message:

"Richard" wrote in message
news On 18/10/2018 13:44, Jim GM4DHJ ... wrote:
"Tim+" wrote in message
...
Jim GM4DHJ ... wrote:
After a puncture and a ruined tyre I tried to put back on an old
28
inch
bike tyre that WAS on the bike years ago only to find its
diameter
was
now
far to big to fit the rim....is this normal ?


Hmm, either the bead wire has broken (on both sides) or you have
simply
mis-remembered which bike or wheel the tyre came off. My money
is on
the
latter.

I've kept many old bike tyres for years and in my experience, the
bead
*never* changes in size. Have you had new wheels put on at any
time
in
the
past? What size did the ruined tyre claim to be in the sidewall?
What
was
the figure printed on the sidewall of the "stretched" tyre?

Tim

come on it says 28 inch on the tyre ,,,,,,and it IS 28 inch bike
....

But are the rims 28inch?

the rims are 28 inch
the tyre was used... I took it off the bike years ago... I only put
it
back
on because the one I was using was destroyed... the tyre said 28
inch.....never mind it is in the bin and a new 28 inch
fitted......no
idea
what happened




There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then

all 700c as far as I know...


That's nearer 26" than 28". As I said, it's most unlikely that the tyre
changed size. Extraordinary claims need extraordinary proof. Post links
to
photos of what is *actually* printed on the sidewalks of your ruined
and
"stretched" tyre please. Tyres just Do Not Stretch in storage.

Tim

OK just been out the back door the one that is too large to fit is on
the bin and the one that does fit is on the bikeobviously...haven't
looked at the sizes myself but I will stand by your findings...thanks

https://www.photobox.co.uk/my/album?album_id=5416389667

they look the same size to me ......????

the destroyed one at the bottom of th bin covered in cat litter which I am
not going to remove from the bin reads 37-622 (28x 15/8x 13/8) ....

If you want I will dig it out of the bin tomorrow and photograph the three
of them side by side......all the same size ......

"Steve Walker" wrote in message
news
One thing about ISO sizes bewilders me: why do they specify the height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to do
it. Surely the three measurements that need to be specified explicitly
a inside diameter (ie diameter of wheel and of bead), outside diameter
(ie of tread) and width. And preferably specify all three in the same
bloody units - either all in mm for Europe (and *maybe* UK) or else all
in inches (for US) - not some half-arsed mixture of the two.

Similar to car tyres then? 205/55R16 has a sidewall height of 55% of 205mm
on a 16" rim. If the second figure is missing, such as 185R13, then the
height is 80% of the first figure.

Exactly. I wonder why the notation isn't (to use your example) 205/113R406,
where 113 = 55% of 205 and 406 is 16" in millimetres. That would use the
same units throughout and would give three independent measurements rather
than having the height being a function of the width.

I could understand it better if the height was a function of the inside
diameter so the OD and ID were (by default = 80%) related by some common
factor. But to relate the height to the width seems weird: why should a tyre
have a greater height just because it's a greater width?

Are all wheel rims the same width, or is it assumed that the width of the
rim/bead will be related by some fixed proportion to the tyre width?

On 18/10/2018 21:35, NY wrote:
"Steve Walker" wrote in message
news
One thing about ISO sizes bewilders me: why do they specify the
height of the tyre (OD - ID) as a percentage of the width? Seems an
odd way to do it. Surely the three measurements that need to be
specified explicitly a inside diameter (ie diameter of wheel and
of bead), outside diameter (ie of tread) and width. And preferably
specify all three in the same bloody units - either all in mm for
Europe (and *maybe* UK) or else all in inches (for US) - not some
half-arsed mixture of the two.

Similar to car tyres then? 205/55R16 has a sidewall height of 55% of
205mm on a 16" rim. If the second figure is missing, such as 185R13,
then the height is 80% of the first figure.

Exactly. I wonder why the notation isn't (to use your example)
205/113R406, where 113 = 55% of 205 and 406 is 16" in millimetres. That
would use the same units throughout and would give three independent
measurements rather than having the height being a function of the width.

I could understand it better if the height was a function of the inside
diameter so the OD and ID were (by default = 80%) related by some common
factor. But to relate the height to the width seems weird: why should a
tyre have a greater height just because it's a greater width?

Are all wheel rims the same width, or is it assumed that the width of
the rim/bead will be related by some fixed proportion to the tyre width?

The width of the rim is also in inches and apparently, a 205/60R15 tyre
is measured on a 6J rim, but is approved for 5.5J to 7.5J - check
manufacturer's info for each make.

The machined face of the wheel for mounting to the hub has an offset
measured from the centreline of the wheel, +ve (toward the outside) or
-ve (toward the inside), in mm.

That all makes far more sense than tyre load indexes (65 = 290kg to 124
= 1600kg, but not in even steps) or speed ratings (A1 to A8 cover very
low speed ratings, B = 31mph, up to Y = 186mph, with the letters
in-between covering the range in-between - mostly, but not completely,
in alphabetical order!)

SteveW

On 18/10/2018 18:16, T i m wrote:
On Thu, 18 Oct 2018 17:45:14 +0100, "NY" wrote:

"Chris French" wrote in message
...
There are two different '28 inch ' tyre sizes though, those with
a bead diameter of 635mm, otherwise known as 700B and those with
a bead diameter of 622 mm, otherwise known as 700C.

You can also get different '26 inch' tyres as well.

Which is why it's always better to refer to tyre size by their ISO
sizes, as no confusion then


One thing about ISO sizes bewilders me: why do they specify the height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to do it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter (ie of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in inches
(for US) - not some half-arsed mixture of the two.

+1

Cheers, T i m


Imperial complication 1 Metric simplicity 0
https://en.wikipedia.org/wiki/Michelin_TRX

"Richard" wrote in message
news
One thing about ISO sizes bewilders me: why do they specify the height
of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to do
it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter (ie
of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in
inches
(for US) - not some half-arsed mixture of the two.

Imperial complication 1 Metric simplicity 0
https://en.wikipedia.org/wiki/Michelin_TRX

When have the French ever done things like the rest of the world? SECAM
television, non-self-cancelling indicators (Citroen), single-spoke steering
wheel, rubber pad for footbrake "pedal" (Citroen again!), "hockey-stick"
dashboard-mounted gear lever (Renault and Citroen).

There is a lot to be said for the world devising a common standard for
things like wheels and tyres, to reduce the variety of sizes that need to be
stocked.

And don't get me started on the pillock who invented the space-saving spare
wheel. If I was "king" I'd make it mandatory that every car had to be
designed to accommodate a spare wheel which was fully-interchangable with
the running wheels, with no speed or distance restrictions, to allow you to
take a flat tyre to the garage when *you* want, rather than being stranded
overnight because you are about to start a long journey (or are even
half-way through it) and you get a puncture late at night or on a Sunday.
And wheelbraces should be cranked, to make it easy to hold the opposite end
with your hand as you apply pressure with your foot on a wheelnut that
refuses to budge; the modern L-shaped ones pull off the wheelnut. And on my
old Peugeot, the long bolt that released the spare wheel from its cage under
the boot had a crude semi-circular notch nut in it, into which you put the
flattened end of the wheelbrace as a crude screwdriver. What a stupid
design - if the bolt jams, you can't apply enough force before the
"screwdriver" jumps out of the notch. How difficult would it have been for
them to put a hexagonal head on the bolt of the same size as the wheelnuts?
That would have been a proper solution.

The one rule about innovating and being different in the hope that people
will adopt your standard is that your non-standard solution must be *better*
than what's already there, not worse :-)

On 19/10/2018 09:32, NY wrote:
"Richard" wrote in message
news
One thing about ISO sizes bewilders me: why do they specify the
height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to
do it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter
(ie of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in
inches
(for US) - not some half-arsed mixture of the two.

Imperial complication 1Â*Â* Metric simplicity 0
https://en.wikipedia.org/wiki/Michelin_TRX

When have the French ever done things like the rest of the world? SECAM
television, non-self-cancelling indicators (Citroen), single-spoke
steering wheel, rubber pad for footbrake "pedal" (Citroen again!),
"hockey-stick" dashboard-mounted gear lever (Renault and Citroen).

There is a lot to be said for the world devising a common standard for
things like wheels and tyres, to reduce the variety of sizes that need
to be stocked.

And don't get me started on the pillock who invented the space-saving
spare wheel. If I was "king" I'd make it mandatory that every car had to
be designed to accommodate a spare wheel which was fully-interchangable
with the running wheels, with no speed or distance restrictions, to
allow you to take a flat tyre to the garage when *you* want, rather than
being stranded overnight because you are about to start a long journey
(or are even half-way through it) and you get a puncture late at night
or on a Sunday. And wheelbraces should be cranked, to make it easy to
hold the opposite end with your hand as you apply pressure with your
foot on a wheelnut that refuses to budge; the modern L-shaped ones pull
off the wheelnut. And on my old Peugeot, the long bolt that released the
spare wheel from its cage under the boot had a crude semi-circular notch
nut in it, into which you put the flattened end of the wheelbrace as a
crude screwdriver. What a stupid design - if the bolt jams, you can't
apply enough force before the "screwdriver" jumps out of the notch. How
difficult would it have been for them to put a hexagonal head on the
bolt of the same size as the wheelnuts? That would have been a proper
solution.

Your spare wheel idea gets my vote.


--
Always smile when walking, you never know where there is a camera ;-)

Remarkable Coincidences:
The Stock Market Crashes of 1929 and 2008 happened on the same
date in October. In Oct 1907, a run on the Knickerbocker Trust
Company led to the Great Depression.

On 19/10/2018 09:32, NY wrote:
"Richard" wrote in message
news
One thing about ISO sizes bewilders me: why do they specify the
height of
the tyre (OD - ID) as a percentage of the width? Seems an odd way to
do it.
Surely the three measurements that need to be specified explicitly a
inside diameter (ie diameter of wheel and of bead), outside diameter
(ie of
tread) and width. And preferably specify all three in the same bloody
units - either all in mm for Europe (and *maybe* UK) or else all in
inches
(for US) - not some half-arsed mixture of the two.

Imperial complication 1Â*Â* Metric simplicity 0
https://en.wikipedia.org/wiki/Michelin_TRX

When have the French ever done things like the rest of the world? SECAM
television, non-self-cancelling indicators (Citroen), single-spoke
steering wheel, rubber pad for footbrake "pedal" (Citroen again!),
"hockey-stick" dashboard-mounted gear lever (Renault and Citroen).

There is a lot to be said for the world devising a common standard for
things like wheels and tyres, to reduce the variety of sizes that need
to be stocked.

And don't get me started on the pillock who invented the space-saving
spare wheel.

https://www.bbc.co.uk/news/uk-england-essex-20984194

If I was "king" I'd make it mandatory that every car had to
be designed to accommodate a spare wheel which was fully-interchangable
with the running wheels, with no speed or distance restrictions, to
allow you to take a flat tyre to the garage when *you* want, rather than
being stranded overnight because you are about to start a long journey
(or are even half-way through it) and you get a puncture late at night
or on a Sunday. And wheelbraces should be cranked, to make it easy to
hold the opposite end with your hand as you apply pressure with your
foot on a wheelnut that refuses to budge; the modern L-shaped ones pull
off the wheelnut. And on my old Peugeot, the long bolt that released the
spare wheel from its cage under the boot had a crude semi-circular notch
nut in it, into which you put the flattened end of the wheelbrace as a
crude screwdriver. What a stupid design - if the bolt jams, you can't
apply enough force before the "screwdriver" jumps out of the notch. How
difficult would it have been for them to put a hexagonal head on the
bolt of the same size as the wheelnuts? That would have been a proper
solution.

The one rule about innovating and being different in the hope that
people will adopt your standard is that your non-standard solution must
be *better* than what's already there, not worse :-)

On 19/10/2018 09:35, Brian Reay wrote:
How difficult would it have been for them to put a hexagonal head on
the bolt of the same size as the wheelnuts? That would have been a
proper solution.

Your spare wheel idea gets my vote.

There is an argument for no spare wheel at all since frankly 50% of the
population can't change one - its an AA (or equivalent) callout and
they are quite capable of asking what tyre size you have and fitting one
at the roadside as trucks have long done

In fact I suspoect that many drivers would be happy with what amnounst
to a total roadside care package ona contract hired car so they dont
have to bother about the car at all. They just phone up when it doesnt
do its stuff.

--
Socialism is the philosophy of failure, the creed of ignorance and the
gospel of envy.

Its inherent virtue is the equal sharing of misery.

Winston Churchill

"Richard" wrote in message
news
And don't get me started on the pillock who invented the space-saving
spare wheel.

https://www.bbc.co.uk/news/uk-england-essex-20984194

Ah good. We know where to send the hate mail ;-)

It sounds like a good idea, but it depends critically on that naive
assumption that "I asked how many times that person had used their spare
wheel. I was told they had never used it." My experience is different.
Driving on poorer country lanes and places where there may be crap on the
road, I have probably had a puncture every couple of years. The other week I
had to go off the edge of a road surface onto a verge to make way for an
oncoming tractor, and there was a lip on the edge of the tarmac with a
wheel-width trough in the grass verge. My wheel went into it and the road
surface gouged a hole in the inner sidewall of my almost brand new tyre. It
was a small enough hole that I didn't notice and completed my journey, but
then found I had a flat tyre a hour later. And I've lost count of the number
of nails that I've had through the tread - lucky most of the time the
puncture has been repairable.

The problem with tyre sealant and inflator packs is that they are only a
get-you-home measure. The tyre can never be repaired and must always be
replaced, whereas with a conventional tyre many punctures can be repaired,
allowing you to get a normal life out of tyre and not having to replace it
while it still has plenty of tread.

I've never yet had a wheel whose nuts I couldn't undo. With a cranked or
cross-shaped wheelbrace it is easy:

- stand at right angles to the car (facing the front or back); I'm going
assume I'm facing forward and changing a nearside wheel, so my right hand is
closest to the car

- do not jack up the wheel yet, it needs to remain on the ground to stop it
turning (especially front wheel on a rear-wheel drive car) as you loosen the
nuts

- in your left hand, hold the opposite end of the wheelbrace to the end with
the nut

- offer it up to the wheelnut with the crank at about 9 o'clock position (as
seen if you were to look towards the wheel)

- raise one foot and place it on the crank, or the end of a side arm (cross
brace)

- press down with your leg while pulling up with your left hand to
counteract the tendency for the wheelbrace to fall off the nut; if brute
strength isn't enough to shift the nut, give it a slight kick until it gives

- once each nut has turned maybe 1/2 a turn, jack up the wheel and loosen
and remove all the nuts (put them somewhere safe like in a hub cap or
wheeltrim)

- now squat down facing the wheel and hold it in your hands at 4- and 8
o'clock position on the tyre tread, with your forearms braced against the
inside of your thighs; ease the wheel off the central boss

- same technique to replace with new wheel

- tighten all the nuts, working in the order 1, 4, 3, 2 (or any order that
isn't consecutive - you want to avoid cyclic stress)

- lower the wheel onto the ground and get back into the original position,
now with the crank in the 3 o'clock position, and fully tighten the nuts

I've done that in about 5 mins per wheel. I've swapped over all four wheels
(exchange nearside front and back, and offside front and back) which needs a
total of 6 wheelchanges (allowing for temporarily fitting and removing the
spare) inside half an hour.

Modern parallelogram jacks don't make it easy because the handle won't stay
extended (it's designed to fold away for storage) and there is so little
ground clearance that I often scrape my knuckles on the ground. A hexagonal
nut on the side, into which you put the wheelbrace, would be so much better,
as you can disconnect the brace and rotate it back from 3 o'clock to 9
o'clock before putting it back on to turn it from 9 to 3 (or vice versa for
lower the jack), for the initial stage when there isn't enough ground
clearance to turn the brace through the lower half of its rotation.

"The Natural Philosopher" wrote in message
news
On 19/10/2018 09:35, Brian Reay wrote:
How difficult would it have been for them to put a hexagonal head on the
bolt of the same size as the wheelnuts? That would have been a proper
solution.

Your spare wheel idea gets my vote.

There is an argument for no spare wheel at all since frankly 50% of the
population can't change one - its an AA (or equivalent) callout and they
are quite capable of asking what tyre size you have and fitting one at the
roadside as trucks have long done

Do the roadside trucks carry a supply of spare tyres of all sizes and the
ability to fit the right tyre to your wheel? I never knew that. I thought
they would just fit your spare and then leave you to find a garage to get
the puncture repaired - assuming garages are open at that time. I've never
had to use the AA or RAC to change a wheel - apart from the one occasion
when I couldn't release the spare wheel from its under-floor cage, due to
the stupid "screwdriver and screw" arrangement that Peugeot used on the 306,
and on that occasion I was able to change the wheel myself. The RAC man said
he'd give me £5 if I could do it quicker than he could have done *using my
wheelbrace, not power tools*. I won :-)

When I reported the puncture to RAC, I wasn't asked what size tyre so the
RAC man could make sure he had the correct size in his van, and he didn't
offer to replace the tyre once he arrived.

I was gobsmacked that my wife would wait for AA, RAC or Green Flag instead
of changing it herself and being on her way in a few minutes. I offered to
show her how I do it, but she said no. The only time I wouldn't change a
wheel is if it's the offside when I'm on the hard shoulder of the motorway,
and even then I'd sacrifice the tyre and crawl along the hard shoulder to
the next junction to find somewhere safe to replace it, or else give it a
quick burst from my electric pump to make it safe(r) to drive on for a short
distance.

On Friday, 19 October 2018 09:32:41 UTC+1, NY wrote:
"Richard" wrote in message
news

When have the French ever done things like the rest of the world? SECAM
television, non-self-cancelling indicators (Citroen), single-spoke steering
wheel, rubber pad for footbrake "pedal" (Citroen again!), "hockey-stick"
dashboard-mounted gear lever (Renault and Citroen).

There is a lot to be said for the world devising a common standard for
things like wheels and tyres, to reduce the variety of sizes that need to be
stocked.

And don't get me started on the pillock who invented the space-saving spare
wheel. If I was "king" I'd make it mandatory that every car had to be
designed to accommodate a spare wheel which was fully-interchangable with
the running wheels, with no speed or distance restrictions, to allow you to
take a flat tyre to the garage when *you* want, rather than being stranded
overnight because you are about to start a long journey (or are even
half-way through it) and you get a puncture late at night or on a Sunday.
And wheelbraces should be cranked, to make it easy to hold the opposite end
with your hand as you apply pressure with your foot on a wheelnut that
refuses to budge; the modern L-shaped ones pull off the wheelnut. And on my
old Peugeot, the long bolt that released the spare wheel from its cage under
the boot had a crude semi-circular notch nut in it, into which you put the
flattened end of the wheelbrace as a crude screwdriver. What a stupid
design - if the bolt jams, you can't apply enough force before the
"screwdriver" jumps out of the notch. How difficult would it have been for
them to put a hexagonal head on the bolt of the same size as the wheelnuts?
That would have been a proper solution.

The one rule about innovating and being different in the hope that people
will adopt your standard is that your non-standard solution must be *better*
than what's already there, not worse :-)


Your proposal would in reality make things worse. Progress depends on trying various changes, many of which don't turn out to be keepers, but some do. Stop that process & you hinder product improvement. Imagine if you'd insisted on a set of universal tyre sizes in 1910, people would have kept driving on 2" wide tyres for years longer than was appropriate. Or again in 1980, tyres have gotten fatter since then to reduce loss of grip incidents.

Re no spare tyre, that does suit some people, some it doesn't. I can't see a sound reason to prevent people making their own choice on whether they carry a spare and what type. AA/RAC/etc can alter their premiums based on spare ownership if they want, but I'm sure they're better off not doing.

Re standardising tyre sizes to less types, the result would be more rubber & cost used pointlessly.

Fwliw I've never liked self cancelling indicators, they always cancel at the wrong time. OTOH I did not like the manual reverse light.


NT

"The Natural Philosopher" wrote in message
news
On 19/10/2018 09:35, Brian Reay wrote:
How difficult would it have been for them to put a hexagonal head on the
bolt of the same size as the wheelnuts? That would have been a proper
solution.

Your spare wheel idea gets my vote.

There is an argument for no spare wheel at all since frankly 50% of the
population can't change one - its an AA (or equivalent) callout and they
are quite capable of asking what tyre size you have and fitting one at the
roadside as trucks have long done

Trucks dont do it like that.

In fact I suspoect that many drivers would be happy with what amnounst to
a total roadside care package ona contract hired car so they dont have to
bother about the car at all. They just phone up when it doesnt do its
stuff.

And plenty wouldnt due to the cost of that.

"NY" wrote in message
o.uk...
"Richard" wrote in message
news
And don't get me started on the pillock who invented the space-saving
spare wheel.

https://www.bbc.co.uk/news/uk-england-essex-20984194

Ah good. We know where to send the hate mail ;-)

It sounds like a good idea, but it depends critically on that naive
assumption that "I asked how many times that person had used their spare
wheel. I was told they had never used it." My experience is different.
Driving on poorer country lanes and places where there may be crap on the
road, I have probably had a puncture every couple of years.

Yeah, I've managed about that. And its much more convenient to be able
to use the full sized spare than wait for the AA equivalent to show up and
given that I can fix most stuff that dies and can usually get a mate to give
me a hand if say the battery dies to get a new one, and our AA equivalent
is happy to let you sign up at the time you need them, I dont bother with
the considerable cost of belonging all the time. I've only ever had to call
them once in more than 55 years of driving, when I managed to come
off the road into an irrigation drainage channel which only had little
water in it and needed the tow truck to pull the car out.

I managed another of those quite recently and the next fella that
passed had a decent ute and snatch strap and pulled me out himself.

The other week I had to go off the edge of a road surface onto a verge to
make way for an oncoming tractor, and there was a lip on the edge of the
tarmac with a wheel-width trough in the grass verge. My wheel went into it
and the road surface gouged a hole in the inner sidewall of my almost
brand new tyre. It was a small enough hole that I didn't notice and
completed my journey, but then found I had a flat tyre a hour later. And
I've lost count of the number of nails that I've had through the tread -
lucky most of the time the puncture has been repairable.

Yeah, most of mine have been. Not all tho. With the Getz it isnt hard
to not even notice a flat and **** the tyre driving on that by the time
you notice its flat.

The problem with tyre sealant and inflator packs is that they are only a
get-you-home measure. The tyre can never be repaired and must always be
replaced, whereas with a conventional tyre many punctures can be repaired,
allowing you to get a normal life out of tyre and not having to replace it
while it still has plenty of tread.

I've never yet had a wheel whose nuts I couldn't undo. With a cranked or
cross-shaped wheelbrace it is easy:

I wouldnt say easy, but certainly doable.

- stand at right angles to the car (facing the front or back); I'm going
assume I'm facing forward and changing a nearside wheel, so my right hand
is closest to the car

- do not jack up the wheel yet, it needs to remain on the ground to stop
it turning (especially front wheel on a rear-wheel drive car) as you
loosen the nuts

Yeah, I always do it like that.

- in your left hand, hold the opposite end of the wheelbrace to the end
with the nut

- offer it up to the wheelnut with the crank at about 9 o'clock position
(as seen if you were to look towards the wheel)

- raise one foot and place it on the crank, or the end of a side arm
(cross brace)

- press down with your leg while pulling up with your left hand to
counteract the tendency for the wheelbrace to fall off the nut; if brute
strength isn't enough to shift the nut, give it a slight kick until it
gives

I used to do it like that with one of those big X shaped wheel braces
before someone mentioned the telescopic ones here. That lets you get
a lot more leverage on the nut and works fine without standing on it.

- once each nut has turned maybe 1/2 a turn, jack up the wheel and loosen
and remove all the nuts (put them somewhere safe like in a hub cap or
wheeltrim)

I dont bother and have never lost one.

- now squat down facing the wheel and hold it in your hands at 4- and 8
o'clock position on the tyre tread, with your forearms braced against the
inside of your thighs; ease the wheel off the central boss

I normally sit on the ground to do that.

- same technique to replace with new wheel

- tighten all the nuts, working in the order 1, 4, 3, 2 (or any order that
isn't consecutive - you want to avoid cyclic stress)

- lower the wheel onto the ground and get back into the original position,
now with the crank in the 3 o'clock position, and fully tighten the nuts

I've done that in about 5 mins per wheel. I've swapped over all four
wheels (exchange nearside front and back, and offside front and back)
which needs a total of 6 wheelchanges (allowing for temporarily fitting
and removing the spare) inside half an hour.

I dont bother to rotate the tyres anymore.

Modern parallelogram jacks don't make it easy because the handle won't
stay extended (it's designed to fold away for storage) and there is so
little ground clearance that I often scrape my knuckles on the ground.

I dont, because mine has a removable handle which is also the supplied
wheel brace, just an L shape. Certainly slow and fiddly initially tho.

I've been toying with the idea of a battery drill kept in the car to
make that more convenient but have decided that its not very likely
that the drill will be charged when I need it every couple of years.

A hexagonal nut on the side, into which you put the wheelbrace, would be
so much better, as you can disconnect the brace and rotate it back from 3
o'clock to 9 o'clock before putting it back on to turn it from 9 to 3 (or
vice versa for lower the jack), for the initial stage when there isn't
enough ground clearance to turn the brace through the lower half of its
rotation.

Or just a normal ratchet socket handle.