I find calipers great for measuring seat posts themselves, not to great for measuring the internal diam of the frame though. The hole can distort up near the top (where the clamp acts). Can easy give you a false measurement.
@jammy started
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I find calipers great for measuring seat posts themselves, not to great for measuring the internal diam of the frame though.
The hole can distort up near the top (where the clamp acts). Can easy give you a false measurement.