How to measure bike size?
06-19-19, 03:14 PM
#1
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How to measure bike size?
The Surly Pacer road bike I purchased was advertised on craigslist as a size 54. However, underneath the crank next to the serial number, "PACER-52" is embossed into the frame, which made me think it's actually a size 52.
The measurement from the crank to the END of the seat tube (where it becomes the seat post) is 54 cm. The measurement from the crank to the center of the top tube is 52 cm. Which is the proper measurement to tell the size of a road bike? Thanks in advance!
The measurement from the crank to the END of the seat tube (where it becomes the seat post) is 54 cm. The measurement from the crank to the center of the top tube is 52 cm. Which is the proper measurement to tell the size of a road bike? Thanks in advance!
06-19-19, 05:28 PM
#2
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The Surly Pacer road bike I purchased was advertised on craigslist as a size 54. However, underneath the crank next to the serial number, "PACER-52" is embossed into the frame, which made me think it's actually a size 52.
The measurement from the crank to the END of the seat tube (where it becomes the seat post) is 54 cm. The measurement from the crank to the center of the top tube is 52 cm. Which is the proper measurement to tell the size of a road bike? Thanks in advance!
The measurement from the crank to the END of the seat tube (where it becomes the seat post) is 54 cm. The measurement from the crank to the center of the top tube is 52 cm. Which is the proper measurement to tell the size of a road bike? Thanks in advance!
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2010 AB T1X ** 2010 Cannondale SIX-5 ** 1993 Cannondale RS900 ** 1988 Bottecchia Team Record ** 1989 Bianchi Brava ** 1988 Nishiki Olympic ** 1987 Centurion Ironman Expert(2) ** 1985 DeRosa Professional SLX ** 1982 Colnago Super ** 1982 Basso Gap ** 198? Ciocc Competition SL ** 19?? Roberts Audax ** 198? Brian Rourke ** 1982 Mercian Olympic ** 1970 Raleigh Professional MK I ** 1952 Raleigh Sports
06-19-19, 05:33 PM
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Check the geometry chart and compare your measurements to it. Should be easy to find on Surly's website.
06-19-19, 06:01 PM
#4
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Thanks guys. I found the geometry chart for this bike: https://www.bicycleroots.com/media/c...469136680.jpeg
Looks like the "seat tube length (center-top)" is 540.0 for the 54cm bike. Which confirms what I measured. Then why would it have "Pacer-52" embossed near the serial number? lol!
Looks like the "seat tube length (center-top)" is 540.0 for the 54cm bike. Which confirms what I measured. Then why would it have "Pacer-52" embossed near the serial number? lol!
06-19-19, 06:09 PM
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Because it’s 52 cm measured center to center?
Read Sheldon’s write up of frame sizing:
https://www.sheldonbrown.com/frame-sizing.html
Read Sheldon’s write up of frame sizing:
https://www.sheldonbrown.com/frame-sizing.html
06-19-19, 09:27 PM
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What's the top tube measurement?
06-19-19, 11:02 PM
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Thanks guys. I found the geometry chart for this bike: https://www.bicycleroots.com/media/c...469136680.jpeg
Looks like the "seat tube length (center-top)" is 540.0 for the 54cm bike. Which confirms what I measured. Then why would it have "Pacer-52" embossed near the serial number? lol!
Looks like the "seat tube length (center-top)" is 540.0 for the 54cm bike. Which confirms what I measured. Then why would it have "Pacer-52" embossed near the serial number? lol!
06-20-19, 06:02 AM
#8
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Measure the HEADTUBE and compare it to manufacturer’s geo chart. When trying to determine frame size, I find that is the easiest measurement to take accurately. If 2 diff frame sizes have same HT lengths (somewhat rare) then I start taking other measurements...
06-20-19, 06:20 AM
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Ever since sloping TTs came into existence, people have been confused about frame size. I measure C to C using "virtual" points and that works for me. My latest bike is a CAAD 12 in size 52. My ideal size is 54-55. I measured virtually and my 52 is actually a 54 and fits me perfectly.
06-23-19, 04:20 AM
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Ever since sloping TTs came into existence, people have been confused about frame size. I measure C to C using "virtual" points and that works for me. My latest bike is a CAAD 12 in size 52. My ideal size is 54-55. I measured virtually and my 52 is actually a 54 and fits me perfectly.
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2010 AB T1X ** 2010 Cannondale SIX-5 ** 1993 Cannondale RS900 ** 1988 Bottecchia Team Record ** 1989 Bianchi Brava ** 1988 Nishiki Olympic ** 1987 Centurion Ironman Expert(2) ** 1985 DeRosa Professional SLX ** 1982 Colnago Super ** 1982 Basso Gap ** 198? Ciocc Competition SL ** 19?? Roberts Audax ** 198? Brian Rourke ** 1982 Mercian Olympic ** 1970 Raleigh Professional MK I ** 1952 Raleigh Sports
2010 AB T1X ** 2010 Cannondale SIX-5 ** 1993 Cannondale RS900 ** 1988 Bottecchia Team Record ** 1989 Bianchi Brava ** 1988 Nishiki Olympic ** 1987 Centurion Ironman Expert(2) ** 1985 DeRosa Professional SLX ** 1982 Colnago Super ** 1982 Basso Gap ** 198? Ciocc Competition SL ** 19?? Roberts Audax ** 198? Brian Rourke ** 1982 Mercian Olympic ** 1970 Raleigh Professional MK I ** 1952 Raleigh Sports
