A good solution sometimes necessitates a radically new beginning!
Eightpins has set itself the goal to tackle major technical flaws in mountain bikes and to correct them. In our view, conventional dropper seatposts have been nothing but provisional retrofit solutions. The operation of dropper seatposts ought to be incorporated into the overall operating system of mountain bikes. For this reason, we have developed a new interface that integrates the dropper seatpost directly into the bike frame. Dropper seatposts are not retrofit solutions anymore!
A seatpost almost as before
The tube of the Eightpins seatpost is very similar to that of a classical seatpost without dropper function. It is mounted directly in the frame and held in the chosen position from the bottom by means of the Eightpins height adjustment unit. The secret lies inside the tube – here are some extras, which are very important for the function of the height adjustment.
No dirt wanted!
The red extension tube serves as a seal and dirt deflector. It is simply plugged on top of the frame seat tube and functions as a holder for the scraper, which swipes dirt from the seatpost tube.
To allow the seatpost to move as freely as possible with minimal friction, it is guided by two sliding bushes. These bushes are mounted in a reduction tube, which is inserted into the frame seat tube from above.
All in one
The height adjustment unit of the Eightpins seatpost includes many important functions: amongst others, a mechanism for height adjustment, a gas spring, an overload clutch and the holding unit of the Postpin mounting system.
We have replaced the old technology of traditional seatclamps by the newly developed Postpin seapost axle system. This axle is directly integrated in the frame for more durability and less weight. Contrary to seatclamps, which squeeze tubes to hold them by friction, the Postpin seatpost mounting system holds the Eightpins seatpost form locked in position. No more sliding or twisting.
The Eightpins seatpost can be ideally fitted to any body height and any riding style. This has been achieved through the possibility to adjust the saddle height and the stroke separately. Particularly, short and medium-sized riders benefit from this asset. Whereas other seatposts coming with complete bikes need to be replaced if either the length or the stroke doesn’t fit, the Eightpins seatpost can simply be adjusted.
By aligning the height and height separately, the rider takes advantage of a full drop in every height adjustment within the stroke capacity of the seatpost.
The stroke can be adjusted to a higher dropped saddle position for the individual needs of different riding styles such as marathon or cross country.
Maximale Sattelstützen-Höhe: 340mm
It is easy to get the Eightpins seatpost adjusted and ready for the trail. Height adjustment is done with a simple 4mm allen key. To reach full drop travel, the seatpost tube can be shortened like a normal seatpost without a dropper function. Just cut it with a saw or a tube cutter.
The possible stroke of the Eightpins seatpost depends on the length of the frame seat tube. Just like any other seatpost, the Eightpins seatpost requires a certain insertion depth in the frame. Depending on the frame height, more or less space can be used for travel between the inserted guiding tube and the Postpin axle. The possible stroke results from: total length – insertion.
The wiser head gives in
The interface of the Eightpins seatpost has an integrated overload clutch. This allows for a twist of the saddle in overload situations such as crashes. The twisted saddle can then be easily turned back into the right position by hand.
The trend in enduro bikes and all-mountain bikes towards shorter chainstays, bigger wheels and more travel is a big challenge concerning the frame design. The seattubes have to move a bit forward to get enough room for the wheels. Eightpins has already developed a seatpost with 23mm setback to compensate the saddle position. This enables a mixture between handy geometry and enough travel for the seatpost.