Adjustable height seat posts have been available for a few years now and while they’re a must-have upgrade, they’re not known for long term durability. In fact, we have yet to get more than a full season of use from any post in our quiver without a rebuild or servicing it. And while some posts, like the Gravity Dropper, are easily serviceable, others can’t be serviced at all, and have to be sent back to the manufacturer for the rebuild.
Fortunately there are more options these days when it comes to posts. More options make for a more competitive market place which means manufacturers will be stepping up their game in order to compete in terms of durability, weight and price. Hopefully in the near future we’ll be riding a post that can handle more than a single season of hard use.
It’s possible that’s already happened. One of the most interesting new options is the Fall Line Dropper Post from 9point8 out of Canada.

One of the best features of the post is the well designed remote that offers multiple mounting options.
While not inexpensive, the Fall Line lists for $379 USD, a competitive price for an adjustable height post.
Features
The Fall Line post is a cable actuated dropper seatpost that utilizes a standard derailleur cable to activate the post. A mechanical brake locks the post in place which is spring activated, so it should perform reliably, even in cold weather. This was a feature I found extremely attractive, after previous issues with hydraulic posts while riding in low temperatures. Utilizing air as the spring, the post is designed for use on bikes with internal ‘stealth’ routing options.
Best of all, it’s available with 125mm or 150mm of drop in both 30.9 and 31.6 post diameters.
Installation
Installation is a bit tricky until you’re familiar with how the post functions. (of course, that could be said with any cycling component) While getting over the learning curve I installed and disassembled it at least four times as I determined the ideal amount of slack to have in the cable, and how short to cut the housing.

Another unique feature of the Fall Line is a no tool required cable connection, that lets you remove the post without having to cut or readjust the cable.
The allen key that holds the cable is quite small, so care is required to avoid over torquing and stripping the bolt.
Figuring out the ideal air pressure took some experimentation to get right as well. The post doesn’t require much to work correctly and works best with a minimal amount of pressure. The post is printed with recommended air pressures listing 20-40psi, but I found a bit less worked best. Instead of going off my air pressure gauge, I went off pump strokes from zero, adding a few at a time until the post retracted at a speed I could live with.
On the trail
The action of the post has been solid — I’m a fan of the thumb lever, and we’ve even considered ordering one to retrofit one of the DOSS posts in our quiver. For comparison, the action and feel of the lever is similar to the KS Lev or Thomson model. It’s a bit longer though, and easier to reach, with a shape that’s nice to the touch. You also have some options in choice of orientation.
The only downside is how the cable points straight out. Because of how it loops, I made the effort to refit and shorten the housing early on. (my usual behavior is to put this sort of thing off until it really bothers me) It keeps the lever design basic though, and the cantilever design should be significantly more durable than other post levers we’ve used. (and broken)
The lever is the one location prone to getting contaminated with foul weather, so I’m hoping it holds up with a minimal amount of maintenance in the wet season with my current, above the bar configuration. On the bright side, it’s just a simple cable and housing, so it should be easy to service.
Initially I had issues with the post staying down and holding its position. A few emails to 9point8 customer service gave a bit of insight into the operation of the post, and to troubleshoot the post I let all the air pressure out in order to verify the mechanical brake was functioning properly.
Fortunately the separate seat clamp/ fore aft adjustment makes it easy to disassemble and access the air valve. It’s a nice feature of the post that made this process quick and easy. Adding air a few strokes at a time, I put in just enough pressure to get the post to raise at an acceptable speed that wouldn’t overpower the locking mechanism.

The seat head uses 4mm titanium clamping screws. To access the air valve, simply loosen one side and remove the other.
After eliminating one possible cause of the issue I decided to just go for a ride and they seemed to go away after a bit of use. At the beginning of my initial rides I could pull the post up or push it down with enough effort, but after logging some ride time these issues disappeared.
A few weeks in and the post has been operating trouble free. I didn’t care for the slow return speed I was experiencing with the minimal air pressure, so I added a few more psi, and that seems to have dialed it in.
Now that mine’s broken in and working properly I’m psyched on it. It’s a good looking post, and works as promised. I’m running the 31.6mm post but it’s also available in 30.9, and as one of the only 30.9mm posts with 150mm of adjustment it’s a stand out product worth taking a look at.
While I primarily purchased one (disclaimer: I did receive industry pricing on mine) to use as a replacement while dealing with sagging issues on an another post, (which I shall not name here) I like it quite a bit and plan to run it for the long haul. Here’s hoping it holds up.
The Fall Line post features a 2 year warranty and has a listed weight of 416g-514g. You’re looking at 507g-605g for the cable, housing, trigger, fluid and post.
Check it out at 9point8.ca
<UPDDATE: 2/26/18>
Other than my complaints with the stock lever/trigger, durability of the post has been outstanding. I’ve been ignoring an issue with air leakage, but as the post needs to be aired up every time I ride the bike, I’ll be troubleshooting it this week, and attempting a repair.