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31.8 QR Seat Post Clamp

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31.8 QR Seat Post Clamp

Old 02-07-18, 07:08 PM
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31.8 QR Seat Post Clamp

If my seat-post is 31.6 would a 31.8 sp clamp be the correct size?
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Old 02-07-18, 07:45 PM
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What are you trying to clamp? If it's the seat tube to secure the post inside, then you want the OD of the top section of the seat tube. Right where the clamp would slide over, differences in clamps' labeled size of about .2mm is common. If you're clamping something to the 31.6mm post then a 31.8mm clamp will likely work. Not sure I answered the real question. Andy
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Old 02-08-18, 06:04 AM
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Originally Posted by koolerb
If my seat-post is 31.6 would a 31.8 sp clamp be the correct size?
No, measure it to get the correct size, suspect that you will need something in the 34-36mm range
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Old 02-08-18, 01:38 PM
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As noted, it's not the seat post diameter you have to match, it's the seat tube outside diameter.
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Old 02-08-18, 07:59 PM
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That makes sense. Tube thickness will vary. The OD of the un-clamped seat tube is roughly 34.6. Glad I asked.
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