Will a 170mm dropper fit a medium E-Sommet frame?

[N1ck]

Brand-X Ascend XL 170mm Dropper Seatpost | Chain Reaction Cycles

Does anyone know if this will fit a medium frame? IE, the overall length. I've got a 2019 e-sommet, and heard some stories about the seat tube being tapered?

 

[Gary]

absolutely it will fit

it probably won't insert fully into the seat tube though. ie. dropper post collar slammed right down to the frame seat tube collar.

What's your inside leg measurement?

I run a 170mm BX on my 2019 small frame.
inserted as deep as it'll go (and extended fully) it's the perfect height for pedalling with a low stack railed saddle. (SLR or Prime) and 165mm cranks
with a taller stack saddle it's too high
My inseam is 33"

I can't really see the medium frame being able to insert the post any further down than my small. (it's down inside the seat tube towards the shock area that restricts insertion depth, not the actual seat tube length.

 

[N1ck]

33" as well.

How much out of the frame does the seat post collar sit on your bike?

 

[Gary]

100mm from top of seat collar to underneath the dropper post seal head

 

[Gary]

You can shim a B-X in a similar fashion to a oneupcomponents post if you only need 10mm or so lower saddle height

 

[N1ck]

Cool, thanks Gary.

 

[R120]

Where are you? I have a 170mm One up that I am currently not using that if you are local to me you can try in the frame.

 

[N1ck]

Hertfordshire, not far from Aylesbury.

 

[R120]

Unfortunately no where near me

 

[Gary]

You can actually feel the taper/step where the seattube reaming ends from below (above the shock) and then you should be able to measure whether the BX 170mm will fit you.
the 170mm BX post is 465mm from rails to post end.
the actuator is around 35mm but doesn't foul the shock when fully bottomed inside the seat tube.

The One Up might cause issues (did in my frame) as they use a funky actuator where the OUTER cable moves rather than the inner meaning it needs more room under the post (and there wasn't space with the shock positioning)


if you need a low stack saddle
Prime Ti (£17.99) or Selle Italia SLR (£100+) are among the lowest around.
Both are very similar shape/size (racey minimalist) the SLR is slightly more flexible/comfortable and up to 50-100g lighter depending on how much money you chuck at it.