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Seatpost length, how to measure?

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Seatpost length, how to measure?

Old 03-01-14, 02:06 PM
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Seatpost length, how to measure?

Obviously one of the points is the bottom end of the post but where is the top measure taken, at the rails, extreme top?
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Old 03-01-14, 02:42 PM
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Nevermind. Found it. Center of Rails to bottom
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Old 03-01-14, 04:22 PM
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useful length is less than total length of course.. you need to have the bottom inside the frame
far enough to span the width of the top tube joint to the bottom of it.
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Old 03-01-14, 06:27 PM
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What you are measuring is total length. Useful length for most seatposts requires the minimum insertion mark to be at or below the top of the seat tube so the useful length is total length minus about 60 to 75 mm. Another exception is the Thomson "Set Back" (i.e. bent) seatpost where the bend must be above the top of the seat tube.
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Old 03-01-14, 06:55 PM
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Thank you everyone for the additional insight.
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