[Closed] Dropper post .. how do you work out max possible travel.

Set you seatpost to your normal max riding height, measure from the saddle rails to your seatclamp, minus an inch.

That's pretty much what your max travel will be.

What's the inch for ???

Most manufacturers will list the extension. Go look at a pic of a dropper and you'll see what the inch might be for (some will need more than an inch).

The inch will be to take account of the space taken up by the collar, seals etc which sit at the top of the fixed portion of the seatpost.

Set your seat to normal ride height, take some measurements from saddle bars to top of seatube then use Alltricks very helpful guide...

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If length G is longer than the distance between the top of your seattube and saddle bars then get a shorter travel dropper eg if the distance between the top of your seattube and saddle bars is 210mm then a 150mm drop Reverb won't fit but a 125mm Reverb will.

I can spot an error in that table above

My 150mm KS i950r, minimum seatpost insertion 'F' is not 100mm. Its more. I think its 120mm

Also bear in mind, that (if correct) for eg, all the reverbs (including the 150mm one) say the 'F' min insert is 80mm. A large amount of frames need more than this
I can't imagine many companies freely willing to warranty a frame that broke because someone was running a 435mm post with only 80mm in the frame?

But the chart can't take in to account every frame on the market. What it does state is the minimum insertion for the dropper post to be functional and safe. 80mm might be adequate for the post, but your frame requires 150mm to comply with its warranty.

So choose one that complies to your frame.