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Syntace p6 Hiflex seatpost

Long distance off road bikepacking and tackling trails on a hardtail can take its toll on the lower back, from the constant trail feedback when seated. Several product options are available of course to help mitigate the feedback into the lower back, all proposing to improve the ride comfort, from suspension seatposts to rigid ones with built in shock absorption. As I have degenerative disc disease and as a consequence, less than ideal lumbar integrity, products are tested beyond simply offering added ‘comfort’, but also their real world impact on the biomechanical deficiency in the lower lumbar spine.

As we know, the less the body has to do to absorb trail feedback and shocks, the less it will fatigue over long distance riding. The ability of the body to absorb shock, unfortunately, reduces as we age too, along with aspects such as flexibility. The lumbar discs are the largest in the body and function to absorb loads and support the weight of our bodies. With degeneration, they lose fluid and the ability to absorb shocks through the spine, along with the surrounding bony and ligamentous structures. The joys of the aging body.

For bikepacking, I like to keep the bike set up as simple as possible, with the least amount of moving parts. Larger volume tyres are of course one way to add comfort, currently running WTB’s 29x2.4 Ranger tyres. Despite the numerous options of suspension seatposts, I just prefer opting for a solid post, mainly for peace of mind of teh simplicity and so that the seatpack straps aren’t going to rub on any moving part. For this reason, I have been trying out the Syntace P6 HiFlex post in its 27.2/400mm size, A post which actually fulfills two purposes, shock dampening and a high degree of adjustability for saddle position.

In hand, the P6 isn’t the lightest carbon seatpost at 212g, but that is actually a positive as I needed confidence that the post was going to survive remote bikepacking trips loaded up without failing. Its internal construction is ovalised in the direction is it designed to flex. The head of the post is molded in as an integral part of the post, again adding confidence for its credentials as being robust. The design bods didn’t stop there. The clamp unit adds a solid and supportive connection with the saddle and post. Being 2 piece, the lower rails are 52mm long for superior saddle rail support and the upper is 30mm allowing for a significant amount of fore and aft adjustment depending on saddle rail design and seat angle. The 2 bolts thread into metal pieces sunk into the upper support unit for secure tightening.

Beyond the proposed dampening properties, the head unit offers a high range of adjustment for bike fitting, perfect if you want to use the P6 across different bikes with different seat angles or simply want to adjust the knee over pedal (KOP) position, to help alleviate lower back issues or if you have a road bike you want to set up in a more triathlon or TT position for example. To achieve this, the lower support is easily removed and swapped around (you’ll have to remove one of the bolts to be able to do this). A really useful, adaptive design that gives maximal support to your saddle rails over some minimalist designs. The clamp will take carbon rails too, up to 11mm. Preferring a more forward KOP position, the Syntace P6 has allowed me to dial in a perfect position on the older style geometry of the mtb, yet I can then use it on the Shand Bahookie with its steeper ST angle by adjusting the clamp piece. With the 2 bolts in line with the direction of force, angle adjustments are quick and easy.

As for its shock absorption and dampening capabilities, it certainly lives up to adding some comfort compared the the inline alloy post that it replaces. I feel like that I can remain seated for longer over rugged terrain without undue lower back issues. Obviously, the more post that is exposed, the more effective the deflection of the post will be under bigger hits and absorbing general trail feedback. You can see just how much it moves by pushing down on the saddle and it works well out on the trail.

Used bikepacking for the Holy Land Challenge, the Atlas Mountain race, the Liguria Bike Trail and general trail riding, I’ve every confidence in the robustness of the P6 post for everyday use and bikepacking duties. It’s light, but not super lightweight, designed instead for durability, its dampening performance and adaptability for getting the saddle in your ideal position. It simply does what it is designed to do and does it well.


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