Dropper seatposts are an ideal example of how fast and far mountain bike technology evolves. Less than 10 years ago, a seatpost that moved up and down was a rarity, but now, it's near impossible to find a mountain bike without one.
What's a dropper post? It's a height-adjustable seatpost that allows you to lower your saddle quickly and easily on the fly by pushing a handlebar-mounted remote.
Why? Mountain biking is a dynamic sport with riders moving all around the bike. Dropping your saddle down gives you much more space to get behind the seat in steep sections, and it greatly improves the bike to body disconnect that allows riders to conquer all sorts of terrain.
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They're not just for getting rad on the descents, a tap of the remote pops your saddle back to the correct height for efficient pedaling, all without having to stop.
Having the ability to gain standover is beneficial for nearly every type of mountain biking. In fact, even gravel and cyclocross riders are embracing the added control, where being able to quickly switch from grinding uphill to attacking a descent is essential.
There are a number of different styles of dropper posts on the market, so we'll run through the main features before showing you the best ones we've tested.
How much travel do I need?
How much the post slides up and down (i.e. travel) the post dictates just how far out of the way you'll be able to get your saddle while still having the best position for pedaling.
Less expensive posts often have less travel. The longer the travel, the stronger and more precise the internal mechanisms have to be.
100mm is the starting point for most dropper posts. That amount of drop makes a noticeable difference, but we've found that longer travel posts do a much better job of maximizing the clearance while maintaining a proper seated pedaling height.
The typical amount of drop is around 100–150mm of travel, which works well for most riders. Longer travel posts do exist, from 170mm up to 200mm, but can be difficult to use for shorter riders or on certain bike frames.
To figure out how long of a drop you can use, measure your existing seatpost from the saddle rail to the top of seat collar, then compare this to the length of the dropper post from saddle rail to below the post's collar.
If the number is the same or less, you're in business. If the dropper post's length is longer, you'll have to use another option.
Travel adjustment options
Fixed or infinite adjustment?
There are two travel styles for dropper posts, those that have fixed height settings that the post stops at (20mm down, 75mm down, etc.) and those that do not, often referred to as stepless or infinitely adjustable.
There are benefits and drawbacks to both. Posts with fixed travel settings allow you to very quickly move the post into the required position without having to hover your rear end on the post until it reaches the correct height.
Stepless posts let you stop the saddle anywhere within the post's travel range. The majority of posts on the market at the moment are stepless designs.
All posts require some sort of spring to return the saddle to the fully upright position and a locking mechanism to hold it in place.
Early designs simply used coil springs and pins to do the job, but these were less refined and often returned the saddle back towards your bottom at an unnerving speed.
It's common to still see mechanically locking designs in conjunction with an air spring, but most designs now use a fully sealed hydraulic cartridge that contains both a pressurized charge and a mechanism that allows the adjustment.
There are a number of advantages to this, namely that the body of the post, which needs to cope with very heavy loads, doesn't also have to be airtight and so lower friction seals can be used for a lighter action.
If something does go wrong with the post, then it's also much quicker and easier to drop in a replacement cartridge rather than repairing the entire post.
On most droppers, lowering the saddle is done by a handlebar-mounted remote.
The remote lever commonly sits under the bar, taking the place of the front shifter paddles on bike's equipped with a single-ring drivetrain. On bikes with a front shifter, remotes that integrate into the lock-on grip collar or sit above the bar are available.
On bargain-priced dropper posts the lever may be just under the saddle on the post's head. The obvious downside to this style is having to take a hand off the bar, something you don't want to do when coming into a section worthy of dropping the saddle.
Most remotes on the market use a cable to operate them but some, such as the RockShox Reverb, use a hydraulic system.
There are drawbacks and benefits to each. Cables are cheap and easy to replace if they fail but over time they become stiffer to use as dirt enters them.
That isn't a problem for hydraulic units, but they are much harder to fix should you damage one in the field.
The overwhelming majority of dropper post cables are internally routed. That requires a hole in the frame to route the cable up through the seat tube; virtually every modern mountain bike, and the latest gravel bikes, have this option.
The other cable option is an external cable that either attaches at the dropper post's collar or up at the head where the saddle attaches.
Benefits of an internally routed cable include clean looks, better protection from dirt and debris, and zero cable movement when dropping the post. But, like any internally routed cable, set up can be tricky and swapping cables and housing can be a chore.
The upsides to an externally routed cable are compatibility with any frame and a more simple set up. The negatives deal primarily with cables that attach to the seatpost head as the cable can interfere with the bike's rear tire or hit your leg if not carefully routed.
Removing the cable from the equation makes installation super easy and also makes swapping the seatpost from bike to bike a reality, provided they share the same seatpost diameter.
Best dropper posts
Fox Transfer Factory
- £383 / $314 / AU$520
- Durable performance
- Smooth, easily controlled travel
- Easy set up
Fox's Transfer Factory dropper post features super reliable cartridge internals and smooth, fast stepless travel.
Fox has covered most of the fitment bases too, with internally and externally routed cable designs and 100, 125 and 150mm travel options on offer.
You get your pick of a 1x specific underbar cable remote or one that works with a shifter. Either way, the remotes are small, well crafted and feature a split clamp for easy install and removal.
The Factory version includes the always blingy gold Kashima coating, which is said to reduce friction. However, you can save some coin and keep it low key, yet keep the same function, with the black anodized Performance model.
9Point8 Fall Line
- £379 / $428 / AU$479
- Unique and interchangeable saddle clamp
- Huge range of travel, 75–200mm options
Dropper posts, especially the first examples, were plagued with reliability issues. Canadian-firm 9Point8 took notice and built the Fall Line dropper post.
It's available in wide range of sizes, 30.9, 31.6 and even 34.9mm diameters and 75, 100, 125, and150mm strokes. There are even 175 and 200mm travel options, but note those posts are very long at 500 and 560mm in length.
Options are nice but more importantly, it's proven to be a durable party post. Even if a problem occurs, the post can be mechanically controlled to get you out of the woods.
Thomson Elite Covert Dropper
- £310 / $480 / AU$632
- Solid, minimal side-to-side movement
- Easy install and set up
- Versatile and small remote
Back in the rigid post days, Thomson Elite seatposts were the absolute benchmark. Thankfully, Thomson brought that high standard to its dropper post.
Travel options are the relatively standard 100, 125 and 150mm, but the travel is extremely smooth and the post has been very reliable. In typical Thomson fashion, the fit and finish is first rate and mature.
The cable remote works well with or without a front shifter. The drop can be stopped anywhere within its travel and there's very little side-to-side saddle movement.
And as a nice bonus, if you have an older frame that takes a 27.2mm post, Thomson is one of very few brands that make an uppy/downy post to fit, though it only comes in an externally routed version.
Specialized Command Post IRcc
- £230 / $350 / AU$500
- Under the bar and grip lock-on collar remotes included
- 10 pre-set indents for repeatable height-adjustment
- Reliable and smooth
Unlike other posts with infinitely adjustable travel, Specialized's Command Post IRcc has a stepped design with 10 increments. Having pre-set positions can make nailing the just-right saddle height over and over easier for some riders.
The saddle height return speed is adjusted by adding or removing air through the bottom of the post, however, it's one of the fastest returning posts out there for better or worse.
Interestingly, Specialized delivers the Command Post with two remotes. The Single Ring Lever bar remote copies the shape and position of a SRAM shifter paddle, making it super easy to find and operate. The lock-on grip collar remote plays nicely with or without front shifters.
The Command Post is available in 75, 100 or 125mm of travel and 30.9 and 31.6mm diameters.
RockShox Reverb Stealth
- £282 / $471 / AU$450
- Super-smooth action
- Excellent remote pairing with SRAM Matchmaker clamp
- Hydraulic fluid instead of cable lessens on-trail repairability
RockShox’s Reverb Stealth looks the same as other dropper posts until you look closely at the remote. Instead of the post's movement being cable-actuated, it's hydraulic.
To make installation easier, RockShox includes its somewhat genius self-sealing Connectamajig plug to join the internally routed hydraulic cable to the bottom of the post. However, if you need to shorten the hose length, the hydraulic bleeding process is much more complicated than changing a cable and housing.
Plus, trail side fixes aren't nearly as straightforward as with a simple cable.
The benefits though are super smooth action that's easy to control and modulate. And barring the occasional hose bleed, no dirt or debris can contaminate the housing causing poor performance.
As far as options go, RockShox has the bases covered with internal and external hose options, three diameters (30.9, 31.6, 34.9mm) and four travel lengths (100, 125, 150, 170mm).
Two remote choices are offered: the original plunger remote didn’t mesh well with Shimano shifters and/or brakes, but the new under the bar 1x remote does. With either choice, pairing a Reverb remote with SRAM’s Matchmaker clamps for its brake levers and shifters equate to a thing of uncluttered beauty.
- £370 / $375 / AU$552
- Revive valve for easy air bleeding
- Short overall chassis height
- Ergonomic remote
Oil for lubrication and air for a spring can be found inside nearly all height-adjustable seatposts. And just like in their suspension cousins, keeping those two separated is an ongoing challenge.
BikeYoke's Revive up/down post features a solution. It uses an air bleed valve at the saddle head. Effectively, the valve allows an escape for the air that gets trapped during the post's cycling up and down. Common problems when air ends up trapped include causing the post to bounce or not return correctly.
Other nice features of the Revive include a long 160mm stroke combined with a short overall post length. This means it's a great solution for smaller frames or frames with a bent seat tube. BikeYoke offers 125, 160 and 185mm travel posts.
In testing, the Revive distinguished itself with smooth action and a lack of any play or looseness at the saddle. However, because of the cable orientation (with the pinch bolt at the post end), installation is a bit more tricky than other internally routed posts.