Eightpins is both the name of this elegant dropper seatpost, and a reference to its eight-pawl mechanical latching system. For those not yet up to speed on the Eightpins concept, it is a mechanically actuated system, designed from the start to be integrated into the seat tube and thus requires a dedicated frame. A seal-head replaces the typical seatpost clamp, and there is an internal sleeve inside the frame which houses the bushings that the post slides on. The aluminum post is 33-millimeters in diameter, so it is stiffer and stronger than a conventional dropper and thus, can safely extend farther out of the frame. The remote is cable actuated and the system is powered by a simple
Eightpins Details • Aluminum, mechanically actuated and user-serviceable • Requires dedicated seat tube design • Oversize, 33mm stanchion tube • Sealed system eliminates clamp • 4 options from 150mm to 220mm • Independent stroke and saddle height adjustments • Internal indexing latches in 6mm increments • 562g to 619g depending upon stroke • MSRP: €495 (without taxes) • Contact: Eightpins
air-spring strut, fixed by a though-bolt near the bottom of the seat tube. Eightpins' integrated dropper is lightweight (50 grams lighter than a RockShox Reverb at 170mm travel), robustly made, and it makes a good case for bike makers to adopt the concept as the next logical step for dropper posts.
The Eightpins seal-head protects the internal sliding bits from grit and grime.
The gas-spring and latching mechanism are attached to the frame with a through-bolt.
Depending upon the size of your bike, you can enjoy up to 220 millimeters of drop that can be customized. Eightpins droppers are purposely shipped longer than most riders will ever use because they are designed to be easily be cut to length and independently adjusted for saddle height and stroke length. Riders can choose to maximize their drop for a given inseam and frame size, or to limit the post's upper and lower range of movement to suit their terrain or riding styles. Technical advantages compared with conventional droppers include longer strokes, lower weight, and a simple, user-serviceable mechanism.
A cut-away view of the Eightpins latching mechanism shows one set of pawls locked into grooves machined into the inner wall of the dropper's stanchion tube.
How It Works
Eightpins is a simple and robust design, largely because its mechanism doesn't need to be squeezed into a 30.6-millimeter tube. The first 100 to 140 millimeters of the frame's seat tube needs to be reamed to accept an insert which houses the post's sliding bushings. The insert is fixed in place by the external seal head. A slender gas strut that is mounted to a through-bolt near the base of the seat tube extends the post. The "Eightpins" latch is mounted to the large, fixed-end of the gas strut.
Latch number one: The Eightpins latch has a pair of keys that slide in tracks machined into the inside of the sliding stanchion tube (just like most droppers do, to keep the saddle aligned). Opposite the keys, however, are a pair of expandable pawls that latch into a ladder of indexing grooves which run the entire length of the inside of the stanchion tube. Each of the pawls have four indexing teeth, hence the name, "Eightpins."
The cable-actuated remote lever retracts the pawls to allow the post to drop or extend and when released, the pawls lock into the indexing ladders. It's a simple and reliable mechanism that offers positive stops, spaced six millimeters apart. It feels very much like an infinitely adjustable post, but the engagement latches with a positive sounding "click."
Use a 2.5mm Allen key to unlock the saddle-height adjustment latch. Turn it 45 degrees and....
...Depress the remote lever to adjust or to remove the stanchion tube. The latch is fixed to the top of the air-spring strut.
Latch number two: Unlike a conventional seatpost, the Eightpins dropper has no external clamp with which to adjust saddle height at full extension. Eightpins handily solved that issue with a second latch that sits on the end of gas strut's shaft. The second latch also locks into the stanchion's indexing ladder. Turning a dial that is nestled into the seat-clamp head unlocks the latch, after which, the user need only to depress the remote lever and the post can be re-positioned up or down to set the saddle height at full extension (or removed completely from the frame). This adjustment only requires a 2.5mm Allen key, used as a lever to poke into a hole in the dial and rotate it. Saddle height can be changed anytime, anywhere.
The height-adjustment dial's 4mm hex-shaft rotates the upper latch to disengage it from the indexing grooves inside the stanchion
Cut-to-Fit Post: Syntace and Liteville were the first-adopters of the Eightpins dropper, so it was fitting that they teamed up to assemble a review bike armed with the system. Liteville sent a medium-size 301 all-mountain bike and, to give me the full experience, they left the Eightpins post uncut at the full 190-millimeters of travel. To get the lowest drop, while maintaining the proper topped-out saddle height, I had to cut the stanchion tube with a hacksaw. The good news was that there is no mechanism inside the stanchion tube, so the operation is about the same as trimming a handlebar or fork's steerer tube. Eightpins furnishes a handy guide that shows how much you can trim, and if you adhere to that, the job takes about fifteen minutes, with most of that time spent washing the shavings from the stanchion tube.
A look down the segment I cut from the stanchion tube shows the seat alignment tracks on either side of the indexing ladders that engage the Eightpins pawls.
I ended up cutting about 80 millimeters from the post, which left me with 152 millimeters of drop. I could have upped that to 160, but I wanted to leave some extra post extension for another test rider whose saddle height is slightly taller than mine. You can deviate from the charts to further maximize your dropper's stroke, but you'll need to follow more detailed instructions, which may include adding bottom-out spacers. The key is to shorten the post as little as practical, without causing the stanchion to bang into the through-bolt when you completely retract it. On the flip side, you also need to ensure that the stanchion overlaps both insert bushings at full extension so the post is safely supported. It's common sense, but some cyclists lack those genes.
Travel options and weights are starting points.
Smooth Push remote lever: I am usually not a fan of radial type remote levers, but Eightpins' version has a very ergonomic shape, with an outward flare that emulates the action of a paddle to some extent, but without taking up as much space. It's called "Smooth Push," and the CNC-machined and anodized remote is furnished with a length of aluminum tubing with an adjustment barrel at one end that can be custom bent by hand to direct the cable housing exactly where it best fits your handlebar arrangement.
Eightpins' radial remote lever actually feels ergonomically correct. It's designed to keep your hand in a more natural position on the grip.
Saddle-impact clutch: The innovations keep coming. Eightpins anticipated that the post or saddle could sustain damage in the event of a crash, so they designed in a simple clutch at the base of the gas spring that will break free and allow the saddle and post to rotate up to 45 degrees right or left upon impact. The rider can then return the saddle to normal with a strong twist. The clutch tension is adjustable.
Offset bushes and saddle clamps: Not all seat tubes will accommodate the unobstructed length that the Eightpins assembly requires, so its designers include offset bushings with the kit that allow the post to accept a small amount of fore/aft misalignment. Saddle clamp-heads are offered with minimal offset (like the RockShox Reverb) and also with a 25-millimeter rearward offset that is intended to let
An offset seat-clamp is an option Eightpins offers to allow frame designers to move the seat tube forward without affecting the rider's position over the bike.
frame designers move the seat tube forward to clear the rear tire at full suspension compression without resorting to the bent tube that is commonly used to solve that issue. The Liteville 301 is designed to take advantage of that feature.
The post's unbroken 33-millimeter shaft rekindles the cleaner lines of the pre-dropper era.
For all the tech it embraces, the Eightpins dropper post is remarkably simple to use. Once I was accustomed to the click sound that the latch makes when it locks in, I rarely thought about it. It takes little effort to depress, and it returns with crisp authority. To establish a mid-drop saddle height for rolling trails, simply keep the lever depressed and let the post follow your movements until your bum is at the chosen height and "click" you're there. When I returned to bikes with conventional hydraulically actuated posts, I found myself occasionally checking to see if they were broken or needed adjustment.
I like how the Eightpin post gives the bike a retro look. The post's unbroken 33-millimeter shaft rekindles the cleaner lines of the pre-dropper era. The remote lever is also a low-profile design, and it has a similar effect on the look of the handlebar. That big stanchion tube feels stiffer than a Reverb or a Transfer at similar extensions and, aesthetically, I like it much more than the slender column of a clamp-on post. To be truthful, I would be perfectly happy to rock my Fox Transfer dropper for the rest of my life, but I wouldn't shed a tear if bike makers adopted integrated droppers, especially if they performed as effortlessly as the EightPins does. It's next level.
Reliability has been a non-issue with the post, which has been racking up miles, mostly in dusty conditions. I've crashed it a number of times and knocked the saddle out of whack, so I got to use the clutch feature. I'm not so sure how beneficial the clutch is for the rider, but if it protects the post, that's okay with me. It takes a fair amount of strength to move. The saddle never went askew from leg pressure while I was riding, which was an initial concern. So far, there is a small amount of fore-aft play in the post at full extension (which has been there from the start) and no rotational play at the saddle at all. It sounds and feels as good as new. I've had it apart for a look at the internals. The wiper seal has done its job, and there are no metal bits floating around the pawls or inside the stanchion tube. Evidently, the folks at Eightpins did their homework.
What if you have to sell your Eightpins equipped bike and the stanchion is cut too short for your potential buyer? Eightpins sells the full-length replacement stanchion tube for €150. What if you get a major sponsorship from a parts maker who wants you to run their conventional dropper? Well, in the case of Liteville, you can purchase a clamp-type seat collar that fits into the same location as the Eightpins' bushing insert and seal-head. The clamp conversion is also insurance for frame owners with worries about being left behind in the race for new technology. For now, Eightpins is well ahead of the curve, and they've designed the post to be easily serviced by its owner. Its parts are simple, and it should be a lifetime investment.
I'm a fan. I like the Eightpins' ease of operation compared to the two most popular conventional hydraulic droppers. I like the fact that it isn't full of oil, and I like their integrated concept. Not surprisingly, its been slow going for Eightpins to break into the OEM market. Presently, Liteville is their major partner, but there is an up-welling of smaller builders, eager to set new trends, who are beginning to displace larger, more established names in the high-end arena. This season may be the turning point for well-vetted innovations like Eightpins' integrated dropper to gain wider acceptance. I certainly hope so.—RC