The seatpost of a MTB, supports the saddle relative to the frame, it provides an adjustment of the height and orientation of the saddle. The MTB seatpost can be fixed, with telescopic shock absorber or adjustable in height with a handlebar control.
How to choose an MTB seatpost?
For use in cross country you will probably be looking for a light and long model. For a use in freeride or cross country you can choice a seatpost whose height can be adjusted to the handlebars, the advantage is to be able to lower your saddle during downhill for better manoeuverability. For use in enduro or downhill you will be looking for a robust model that allows a recoil of the saddle compared to the handlebar.
Here are some brands: race face, ritchey, BBB, ...
Compatibility of a MTB seatpost:
The fixing of a mtb saddle is standard, it is done by the two rails located under the saddle on which is fixed a saddle carriage secured to the tube of the seatpost. On the other hand, there are many seatpost diameters. To make the right choice it is necessary to precisely determine the inner diameter of the seat tube of the frame in order to determine the outside diameter of the corresponding MTB seatpost. For maximum accuracy we recommend a measurement with a caliper.
The length of the MTB seatpost is also a parameter to take into account because in mountain biking it is agreed that the length of the tube outlet from the frame is at least minimum 15 cms.
The assembly of a seatpost on a MTB requires a standard tool, generally an allen wrench for adjusting and tightening the saddle and the seat clamp. Please respect the tightening torques values recommended by the manufacturers in order to not damage the screwed items.
Maintenance and replacement of a MTB seatpost:
A rigid MTB seatpost does not require any particular monitoring, however regular cleaning prevents the accumulation of soil and pollutants in the saddle carriage and its fixing screw. For shock-absorbing or height-adjustable models, it will also be necessary to clean the gaskets and bellows very regularly and to lubricate the moving parts. Check for leaks as this type of seatpost may contain a hydraulic system. Replace failed seals or bellows.
In the event of a fall, it is recommended to check the tightness of the saddle and any defects: deformation of the seatpost tube, cracks on the carbon, leakage, tearing of the bellows, scratches on the moving parts ... if the tube is deformed, or if a defect no longer allows the desired adjustment of the saddle to be obtained, then the MTB seatpost will have to be replaced.