Dropper Seat Post 31.6 mm/30.9 mm Tranzx YSP18

This TranzX YSP18 seat post is made of aluminium 6061 for a weight of 600 g.

It has a length of 400 mm and a 15 mm offset head (seat clamp size).
That results in a maximum height inserted at the insertion limit of 281 mm for a stem with 120 mm of travel (or 318 mm for 150 mm travel).

The seat post has an interface for two saddle rails with a 43 mm centre distance spread. This is the most common interface in the cycling world, and you shouldn't have any issues with saddle compatibility. Be sure to respect the limits displayed on your saddle rails. The clamp should not be too far forward or backwards. The seat clamp should be tightened between 8 and 10 N.m.

Be sure to find a saddle that suits your practice and your body type (pelvis width, etc.).

Your dropper seat post has an offset control that gets placed on the handlebar. The cable routing can only be done internally. So you need to run a cable from the control to the seat post, going through the inside of the frame and the seat post.

Your control can be installed on the right or the left side of the handlebar, but it was designed to be installed on the left for a single chainring drive train (which has no controls for a front derailleur). Once installed, the seat post control is located underneath the handlebar for better ergonomics.

This dropper seat post is available in two travel sizes: 120 mm and 150 mm.

The travel should essentially depend on your size and/or the size of your bike. For example, we recommend a travel of 120 mm for size S and M bikes, and 150 mm for size L or XL. But that can also depend on your feeling and your practice: a Cross-Country competitor will prefer a dropper seat post with less travel, while an endurance rider will prefer greater travel.

This dropper seat post has a standard format with a 31.6 mm diameter (also available in 30.9 mm). Check that your seat post fits this size.

Take care to respect the insertion limit on your seat post. For the post with 120 mm travel, the insertion limit is 80 mm, and for the post with 150 mm travel, the limit is 120 mm. That means that the seat post must be inserted by at least 80 mm or 120 mm.