Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

General Cycling Discussion Have a cycling related question or comment that doesn't fit in one of the other specialty forums? Drop on in and post in here! When possible, please select the forum above that most fits your post!

User Tag List

Reply
 
Thread Tools Search this Thread
Old 01-29-11, 12:19 PM   #1
flanso 
Senior Member
Thread Starter
 
Join Date: May 2008
Location: NYC
Bikes: Gunnar Sport
Posts: 225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
What does the "C" mean in a tire size

Some tires have the letter C following the width, 700 x 25c, for example. What does the C mean?
flanso is offline   Reply With Quote
Old 01-29-11, 12:23 PM   #2
Shimagnolo
Senior Member
 
Shimagnolo's Avatar
 
Join Date: May 2008
Location: Zang's Spur, CO
Bikes:
Posts: 7,711
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 364 Post(s)
http://www.sheldonbrown.com/tire_sizing.html#french
Shimagnolo is offline   Reply With Quote
Old 01-29-11, 12:42 PM   #3
JanMM
rebmeM roineS
 
JanMM's Avatar
 
Join Date: Jan 2006
Location: In Central IN
Bikes: RANS V3, RANS V-Rex, RANS Screamer
Posts: 13,529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Can't remember if that is for Centrigrade or Celsius.
Trust Sheldon.
__________________
RANS V3 - Ti, RANS V-Rex - cromo, RANS Screamer - cromo
JanMM is offline   Reply With Quote
Old 01-29-11, 12:43 PM   #4
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 22,221
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1146 Post(s)
Guess they forbid teaching the Metric system in Florida,

as another step towards a UN world government.







by the way the C needs to be behind the 700, not the 25..

actual would be 622-25, imprinted on the tire; ... ETRO Standard, bead seat diameter and tore width in mm.

Last edited by fietsbob; 08-02-13 at 08:49 AM.
fietsbob is offline   Reply With Quote
Old 01-29-11, 12:46 PM   #5
Shimagnolo
Senior Member
 
Shimagnolo's Avatar
 
Join Date: May 2008
Location: Zang's Spur, CO
Bikes:
Posts: 7,711
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 364 Post(s)
Quote:
Originally Posted by fietsbob View Post
Guess they forbid teaching the Metric system in Florida,
Perhaps you should read the Sheldon link I posted, before criticizing other people.
Shimagnolo is offline   Reply With Quote
Old 01-29-11, 01:15 PM   #6
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 22,221
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1146 Post(s)
I'm bilingual, fractional and metric, and not humor impaired..
no, It was the South I was making the joke about.
their leaders are usually talking weird.
fietsbob is offline   Reply With Quote
Old 01-29-11, 04:00 PM   #7
flanso 
Senior Member
Thread Starter
 
Join Date: May 2008
Location: NYC
Bikes: Gunnar Sport
Posts: 225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Take a look at the Nashbar site, http://www.nashbar.com/bikes/TopCate...27_-1_200276_N
Expand "by size" on the left side of the page. You will see, for example, separate listings for 700x23 and 700x23c. The same for many other widths; some with c and some without. My question is, whats the difference between the sizes with and without the c?
flanso is offline   Reply With Quote
Old 01-29-11, 04:05 PM   #8
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 27,217
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 575 Post(s)
Quote:
Originally Posted by flanso View Post
Take a look at the Nashbar site, http://www.nashbar.com/bikes/TopCate...27_-1_200276_N
Expand "by size" on the left side of the page. You will see, for example, separate listings for 700x23 and 700x23c. The same for many other widths; some with c and some without. My question is, whats the difference between the sizes with and without the c?
No difference. Strictly a data entry / database records anomaly.
LesterOfPuppets is offline   Reply With Quote
Old 01-29-11, 04:06 PM   #9
Pobble.808
alleged person
 
Pobble.808's Avatar
 
Join Date: May 2006
Location: Lost in Space
Bikes: 1970s Royal Scot 3-Speed, 2005 Breezer Villager 7-Speed IGH
Posts: 451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Shimagnolo View Post
Perhaps you should read the Sheldon link I posted, before criticizing other people.
It looks like there has been a misunderstanding here. If I read Sheldon's link correctly, he was referring to the ABCDs that follow the tire's three-digit diameter dimension (700C, 700D etc). The OP was asking about the c in 700 x 25c, which presumably refers to the nominal width in centimeters.
Pobble.808 is offline   Reply With Quote
Old 01-29-11, 04:06 PM   #10
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 27,217
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 575 Post(s)
Quote:
Originally Posted by fietsbob View Post
Guess they forbid teaching the Metric system in Florida,
The "c" on tire sizes has nothing whatsoever to do with the metric system.
LesterOfPuppets is offline   Reply With Quote
Old 01-29-11, 04:07 PM   #11
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 27,217
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 575 Post(s)
Quote:
Originally Posted by Pobble.808 View Post
It looks like there has been a misunderstanding here. If I read Sheldon's link correctly, he was referring to the ABCDs that follow the tire's three-digit diameter dimension (700C, 700D etc). The OP was asking about the c in 700 x 25c, which presumably refers to the nominal width in centimeters.
A 25 cm tire would be almost 10" wide.
LesterOfPuppets is offline   Reply With Quote
Old 01-29-11, 04:19 PM   #12
Pobble.808
alleged person
 
Pobble.808's Avatar
 
Join Date: May 2006
Location: Lost in Space
Bikes: 1970s Royal Scot 3-Speed, 2005 Breezer Villager 7-Speed IGH
Posts: 451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by LesterOfPuppets View Post
A 25 cm tire would be almost 10" wide.
Good point, but the c in 700x25c is presumably not the same as the 700C etc -- so what is it?
Pobble.808 is offline   Reply With Quote
Old 01-29-11, 04:22 PM   #13
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 27,217
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 575 Post(s)
I always figured they were the same C, just put in the wrong place by someone.
LesterOfPuppets is offline   Reply With Quote
Old 01-29-11, 04:26 PM   #14
009jim
Senior Member
 
009jim's Avatar
 
Join Date: Feb 2008
Location: Australia
Bikes: Giant CRX3, Trek 7100
Posts: 1,288
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'll take a shot at this and suggest that "c" could be a measure of the height to width ratio.
009jim is offline   Reply With Quote
Old 01-29-11, 04:54 PM   #15
prathmann
Senior Member
 
Join Date: Nov 2008
Location: Bay Area, Calif.
Bikes:
Posts: 6,235
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 154 Post(s)
LesterOfPuppets is correct - the 'c' following the tire width (given in mm) is just incorrect but unfortunately the error is becoming more common and has been copied by some tire manufacturers who should know better. As Sheldon's site states, the 'c' in wheel diameter sizes (700c, 650c) was originally an indication of the width with a variety of possible sizes 700a, 700b, 700c, etc. each having about the same total diameter, incl. the tire, but with varying tire widths. Only the 'c' size has survived of the various 700x sizes, but we still have both 650b and 650c. There is no reason for anyone to put a 'b' or a 'c' behind the tire width.

Things would be much clearer if we all switched to the ISO specifications giving the actual bead seat diameters of the rim in mm, i.e. 23-622 is a tire with a width of 23mm that fits on a rim with a bead seat diameter of 622mm.
prathmann is online now   Reply With Quote
Old 01-29-11, 05:40 PM   #16
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Posts: 26,914
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 213 Post(s)
Quote:
Originally Posted by LesterOfPuppets View Post
The "c" on tire sizes has nothing whatsoever to do with the metric system.
Yeah, it's actually more closely related to shoe width sizes as in ABCD.
Retro Grouch is offline   Reply With Quote
Old 01-29-11, 07:05 PM   #17
JanMM
rebmeM roineS
 
JanMM's Avatar
 
Join Date: Jan 2006
Location: In Central IN
Bikes: RANS V3, RANS V-Rex, RANS Screamer
Posts: 13,529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Agree that the 'c' just serves to confuse people. I'll take my 700 plain, please.
__________________
RANS V3 - Ti, RANS V-Rex - cromo, RANS Screamer - cromo
JanMM is offline   Reply With Quote
Old 01-29-11, 08:36 PM   #18
BlazingPedals
Senior Member
 
BlazingPedals's Avatar
 
Join Date: Dec 2004
Location: Middle of da Mitten
Bikes: Trek 7500, RANS V-Rex, Optima Baron, Velokraft NoCom, M-5 Carbon Highracer, homebuilt recumbent
Posts: 9,099
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Quote:
Originally Posted by JanMM View Post
Agree that the 'c' just serves to confuse people. I'll take my 700 plain, please.
If you're going to get rid of the ABCD, then just go by the ETRTO. Instead of 700C, call it what it is: a 622mm rim. It's already on the tire.
BlazingPedals is offline   Reply With Quote
Old 01-29-11, 09:24 PM   #19
JanMM
rebmeM roineS
 
JanMM's Avatar
 
Join Date: Jan 2006
Location: In Central IN
Bikes: RANS V3, RANS V-Rex, RANS Screamer
Posts: 13,529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
I've learned to talk about 406 and 559 so why not 622? Course, that will confuse some folks, too.
__________________
RANS V3 - Ti, RANS V-Rex - cromo, RANS Screamer - cromo
JanMM is offline   Reply With Quote
Old 01-30-11, 01:07 AM   #20
CB HI
Cycle Year Round
 
CB HI's Avatar
 
Join Date: Mar 2005
Location: Honolulu, HI
Bikes:
Posts: 12,349
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Quote:
Originally Posted by fietsbob View Post
Guess they forbid teaching the Metric system in Florida,

as another step towards a UN world government.
Quote:
Originally Posted by fietsbob View Post
I'm bilingual, fractional and metric, and not humor impaired..
no, It was the South I was making the joke about.
their leaders are usually talking weird.
I agree with you. Such foolish post as yours are very humorous.
__________________
Land of the Free, Because of the Brave.
CB HI is offline   Reply With Quote
Old 01-30-11, 01:12 AM   #21
CB HI
Cycle Year Round
 
CB HI's Avatar
 
Join Date: Mar 2005
Location: Honolulu, HI
Bikes:
Posts: 12,349
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Quote:
Originally Posted by JanMM View Post
I've learned to talk about 406 and 559 so why not 622? Course, that will confuse some folks, too.
But learning the ISO numbering can save a person from buying the wrong size tire.
__________________
Land of the Free, Because of the Brave.
CB HI is offline   Reply With Quote
Old 01-30-11, 07:38 PM   #22
Jeff Wills
Insane Bicycle Mechanic
 
Jeff Wills's Avatar
 
Join Date: Mar 2008
Location: other Vancouver
Bikes:
Posts: 8,068
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 75 Post(s)
Quote:
Originally Posted by LesterOfPuppets View Post
No difference. Strictly a data entry / database records anomaly.
Agreed. Interpreting and straightening out databases of bicycle parts information used to be my job (long ago, at Bike'alog). Unless the tire is really unusual, 700 x **C is the same as 700 x **.

I agree with Blaze, too: ETRTO makes life easy. It makes explaining the compatibility of 700C tires (such as 700x35C aka 35-622) and 29" tires (such as 29 x 2.0" aka 55-622) much easier to comprehend.
__________________
Jeff Wills

Comcast nuked my web page. It will return soon..
Jeff Wills is offline   Reply With Quote
Old 08-01-13, 09:08 PM   #23
killerB
Junior Member
 
Join Date: Jan 2008
Bikes:
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I know this is an old thread, but since it's currently the first hit that comes up in The Google:

From The Wikipedia:

ISO 5775-2 defines designations for bicycle rims. It distinguishes between
  • Straight-side (SS) rims
  • Crochet-type (C) rims
  • Hooked-bead (HB) rims
Rims are designated by their nominal rim diameter and their nominal width, separated by a cross (). Both are measured in millimeters. The rim type codes SS or HB precede the rim designation, whereas code C is appended to the nominal width.

Examples:

SS 40020, HB 42225, 62013C

The nominal width of a rim is the inner width between the straight sides or beads as one can easily measure it with a caliper (see the standard for drawings and exact measurement procedures).



The standard widths of straight-side rims are:

18, 20, 22, 24, 27, 30.5The standard widths of crochet-type rims are:
13C, 15C, 16C, 17C, 19C, 21C, 23C, 25C

http://en.wikipedia.org/wiki/ISO_5775
killerB is offline   Reply With Quote
Old 08-01-13, 09:19 PM   #24
LesterOfPuppets
cowboy, steel horse, etc
 
LesterOfPuppets's Avatar
 
Join Date: Sep 2008
Location: Rock Springs, WY
Bikes: My War
Posts: 27,217
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 575 Post(s)
Quote:
Originally Posted by killerB View Post
I know this is an old thread, but since it's currently the first hit that comes up in The Google:

From The Wikipedia:

ISO 5775-2 defines designations for bicycle rims. It distinguishes between
  • Straight-side (SS) rims
  • Crochet-type (C) rims
  • Hooked-bead (HB) rims
Oh boy. I always thought Crochet meant "hook" in French. How much more confusing can this possibly get?
LesterOfPuppets is offline   Reply With Quote
Old 08-01-13, 09:28 PM   #25
ThermionicScott 
Gratuitous glib and snark
 
ThermionicScott's Avatar
 
Join Date: Aug 2011
Location: CID
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers)
Posts: 14,107
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 418 Post(s)
Oh good, a thread bumped to add incorrect information.
__________________
Quote:
Originally Posted by chandltp View Post
There's no such thing as too far.. just lack of time
RUSA #7498
ThermionicScott is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 12:32 AM.