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What is the top tube length c-c of the bike and the seat tube length of a bike?How do i find this out? I'm trying to resell a bike and i've recieved this question.
 

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Cycling induced anoesis
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Jos123 said:
What is the top tube length c-c of the bike and the seat tube length of a bike?How do i find this out? I'm trying to resell a bike and i've recieved this question.
Measuring seat tube c to c would mean measuring from the center of crank 'bolt' to where the seat tube/ top tube meet (at the center) - measuring along the ST. If it's a compact (sloping TT) frame, you'll need to specify that and/ or measure to the 'virtual line' (where the ST/ TT junction would be if the TT were horizontal). You need a level (or straight edge) running parallel along the TT to get an accurate measurement for this.

Measuring top tube c to c would mean measuring from the center of the head tube to the center of the seat tube (or post, if the TT slopes) measuring along the TT.

Or, if possible, try finding the geometry chart of the brand/ model you're selling. Those measurements will likely be included.
 

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Cycling induced anoesis
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Jos123 said:
its a 1984 bianchi. Idk if they'd have the charts.
I did a quick google search and didn't find any, but (generally speaking) bikes of that era were pretty square, meaning that a 52cm frame size would measure close to 52cm's in both seat tube and top tube length. This was true of my '84 Bianchi Limited.

That aside, a bike with traditional geo (horizontal TT) like yours is relatively simple to measure, following what I outlined previously.
 

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Measure from the center of the stem where it goes into the head tube to the center of the seat post and keep the tape or other measuring tool as close to horizontal as you can. If it's SAE (inches) you can convert it ti metric by multiplying by 2.54.
 
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