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Looking here:
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at a 380mm length, 125mm drop post, is [b]G[/b] @ 195mm the measurement from [i]top of seat post clamp[/i] to the [i]bottom of the seat rails[/i]?
As i'm unsure what [i]hauteur du chariot[/i] means.
With my current rigid post, i can ride it at a [u]maximum[/u] height of 195mm from top of seat clamp to bottom of saddle rails, but no more, so a 125mm could just fit.
Failing that i guess i'm looking at a 100mm post.
Using a Fizik Gobi, so i guess i'd need to stick to that (no longer make my model) or a lower height saddle. Which, speaking aloud, may make a 100mm post a [i]safer[/i] buy.
Ta
I would say that the top-most line represents the seat rails, which would be about 35mm above the top of the free stroke of the post.