Syntace P6 HiFlex Seatpost

As a brand, Syntace may not pack the glossy marking punch of names like Race Face, Crank Brothers, Answer orEaston. Their website lacks exciting videos, stunning action photography and lists of pro riders who are paid to use the gear. Instead they include lots of technical information on their product and the why it is made in a particular way.

Take their handlebar stem specifications for example; rather than showing one sample weight in the shortest possible length, they list a separate weight for each incremental change in stem length. Not a big deal in itself but it shows where they are coming from; fanatical German design that’s done from an engineering rather than a marketing perspective.

Engineering Overload

The development timeline behind their new P6 Carbon HiFlex seatpost is a good example of how their design team works. There’s been a carbon post in the Syntace line-up for many years but it had an alloy head that was bonded to a carbon shaft and it weighed around 235g in a 30.9x400mm size. In 2009 I saw a pre-production version of the full carbon P6 post on display at theTaipeibike show—it was due for release shortly thereafter. The new post was around 30g lighter than the earlier carbon/alloy model yet possessed sufficient strength to uphold the 10-year warranty that Syntace provides with most of their products.

However, at the time the market was moving towards seatposts that were made to flex for added comfort—certainly a very desirable feature on hardtails. Observing this, and knowing that their post was strong but not exactly flexible, Syntace went back to the drawing board.

They got a number of ‘flex posts’ from other manufacturers and their SP-3 ‘Red Monster’ fatigue testing machine was put to work. What they found was most flex posts were correspondingly weak, with the ‘give’ occurring in one particular spot. Syntace turned their attention to finite element analysis, tested different lay-ups and employed load oriented material distribution as well as impact and fatigue testing on the SP-3. All up it has taken them three years of development to get this redesigned seatpost onto the market, not to mention the time and effort that was put into the original full-carbon P6 that never saw official production—can you say anal retentive?

The end product is said to pass all of their strength and durability tests whilst offering controlled flex that is distributed along the exposed length of the post. Being a ‘load oriented’ design it is actually made to flex in a fore-aft plane but not from side to side. Have a look up the inside and you’ll see the wall thickness forms an elliptical profile which contributes to this directional flex.

Level Headed

While all of this high-tech design sounds neat, the key feature remains the clamp. It’s the same design that Syntace has employed on all of their posts in years gone by. The twin-bolt head makes fine tuning the saddle tilt extremely easy, and unlike many similar designs, the seat rails can be fitted without removing the bolts. Compared to many featherweight seatposts, the Syntace clamp is solid and sturdy. It clamps the saddle with authority and offers 53mm of support to the underside of the rails—this means crashes and mistimed landings are less likely to lead rail damage.

The topside of the clamp is comparatively narrow (30mm), with a rearward offset. So while the P6 may look like a ‘zero-offset’ post, it offers greater scope for rearward adjustment than you might expect. It is also compatible with oval cross sectional seat rails up to 11mm in height.

With a full carbon shaft, forged alloy head and titanium bolts, our 30.9mm P6 HiFlex weighed 203g in a 400mm length (189g once cut to 350mm). Looking at it purely from a weight-for-dollars perspective, the $269 P6 is around 40g heavier than some minimalist alloy twin-bolt seatposts that sell for half as much. However, most of these cheap but light offerings suffer compromised performance; they can be creak-prone, frequently come loose and apply point-loads that will damage lightweight saddle rails—I’ve experienced all of these things firsthand and even had a saddle fall off on one occasion! The Syntace head is more akin to theUSmade Thomson design but with better underside rail support and more scope for adjustment. It is lighter than most but first and foremost it is bombproof and dependable.

So what of the tuned-in flex that Syntace spent three years developing? To test this I mounted the HiFlex to a hardtail and placed a load on the saddle. I then measured how much the seatpost head flexed rearwards in relation to a fixed point on the frame. I tried a range of posts, both alloy and carbon and most flexed between 2-4mm. The HiFlex moved around 5mm rearwards, offering noticeably more give than most. One 160g alloy post offered the same amount of flex but most of the movement was in the rail clamping mechanism. With the P6 the flex occurred evenly over the length of the post. The only issue with the evenly distributed flex is that the amount of give will vary depending on how much seatpost you’ve got out of the frame (unlike posts that flex at localised point).

The HiFlex feature was apparent when mounted to my hardtail but went by relatively unnoticed on my dually—I’m sure it still helped but it just became less obvious. In any case there was absolutely no downside due to the tuned-in flex. There was no side-to-side sway and the clamping mechanism was always rock solid, creak and wiggle-free.

There aren’t too many 200g seatposts that come with a 10 year warranty and the pricing is consistent with the top-end carbon offerings from most of the big-name brands. Add to that the well-engineered, easy to live with clamp and enhanced comfort, and the P6 HiFlex puts forward a convincing argument—I think it could well be the best lightweight seatpost on the market.

EightyOneSpices (08) 8388 3581 / www.eightyonespices.com.au