Droppers are no longer just for enduro racers. Today, dropper posts can be found on everything from fat bikes to road bikes, used by riders of all different skill levels. Dropper posts eliminate the need to choose between efficiency and handling confidence by allowing you to have the best of both worlds with the flick of a switch.

In this article we will look at the differences in dropper posts and their applications.

Sizes:

The first thing to look at when selecting a dropper is the size. There are three important numbers here which have to do with what size seat-tube it will fit in, the overall length of the post, and how much “drop” it has.

The smallest number is almost always the diameter of the post (I say almost because some posts are getting a shorter and shorter ‘drop’). This is key to making sure the post will fit in your frame.

The next number is typically how much the post will drop. This is key to the type of riding you will be doing and the goal you are looking to accomplish by adding a dropper to your bike. We’ll get more into this later.

Finally, the last and always largest number is the overall length of the post, when it is fully extended. This is key for rider fit and making sure that your seat-post is not too long or too short when in the fully extended, normal riding position.

Example: 27.2mm; lowering: 80mm; 400mm

Activation:

Another key factor when selecting a dropper is how it is activated. Certain types of activation will only work on certain frame types. There are three common types of dropper activation:

Remote – Internally Routed 

The term “remote” means it is activated by a lever usually mounted on the handlebars and connected to the dropper via cable. This type of remote connects to the dropper from within the frame, and therefore the cable needs to be routed inside of the frame. This is a great, sleek design. However, it will only work if the frame already has an un-used cable port somewhere near the head-tube for the dropper cable to enter the frame. There is no need for an exit port, as the end of the cable will attach to the base of the dropper from within the seat-tube.

Remote – Externally Routed

This type of remote dropper is very similar to the one described above, except the cable attaches to the outside of the seat-post and therefore is routed external of the frame. While in theory this type of dropper can be mounted on any kind of bike since there is no need for additional cable ports in the frame; it is highly recommended the frame have some sort of eyelets or other means to anchor the additional cable to the side of the frame. This is especially key on carbon bicycles as excess cable slap can damage the carbon, as can more informal anchoring methods like zip-ties.

Lever

This type of dropper will have some kind of lever on the seat or post itself that is grabbed to activate the post. It will work on any bike and is incredibly simple to install, but the one obvious disadvantage is that the rider has to remove a hand from the bars and grab the post in order to raise or lower the seat.

Applications:

Enduro/All-Mountain:

This type of riding is really what the dropper was originally created for. It allows you to have the seat at a normal XC height for optimal pedaling efficiency and then easily drop it for steep and rough descents. This allows the rider to get back and low over the bike, much like he or she would be able to on a downhill bike.

Droppers for this application often have the biggest “drop” distance, providing the lowest saddle height possible for descending.

Hardtail/XC

The hardtail or cross-country bike seemed to be the next evolution of the dropper post. It began being used in these settings for two reasons:

  • Provide new mountain bikers with added confidence by allowing them to easily drop their saddle and improve their maneuverability atop the bike when reaching technical sections of trail.
  • Provide an advantage on highly technical XC trails.

Droppers being used in XC applications are often lighter and provide less “drop”. Lowering the saddle 1”-4” can provide a big difference in handling and confidence without completely eliminating pedaling efficiency.

Road/CX/Gravel

This seems to be the final evolution of the dropper. Different than all other dropper applications, we are seeing droppers being used in this genre of cycling to actually increase pedaling efficiency over rough terrain. These droppers are lightweight and typically only provide an inch or two of drop.

While racing over extremely rough terrain, one of the biggest challenges is maintaining steady power into the pedals while getting kicked and bounced around. By dropping the saddle just an inch, it allows the rider to lift him or herself above the saddle a small amount while still maintaining steady power into the pedals. Not to mention, it can save loads of energy over a long, grueling race on cobbles or gravel.

This does have the exception of events like Grinduro, where a more traditional dropper for a more traditional purpose would be utilized on a gravel bike.