BMC GF01 seatpost minimum insertion

[Oswald]

I'm thinking of cutting my seatpost to save a little weight.

If you look at this picture, how deep would you want the seatpost to be inserted?
The point where the seat tube meets the top tube is position 1, where it meets the little junction is 2, and where it meets the seat stays is 3.
The seatpost is currently deeper then position 3. I was thinking of cutting it between 2 and 3.

[Causidicus]

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[5 8 5]

If you've got the BMC seatpost use the minimum insert distance as the guide.