Trek’s Favorite Dropper PostM4Bontrager1

Bontrager components are almost synonymous with Trek bicycles; however, the Bontrager brand has a rich history dating back to the early ’80s. The founder, Keith Bontrager, is famous for his aphorism, “strong, light or cheap; pick two.” In the beginning, Keith would hunt for old broken bike parts so he could reverse-engineer them and find ways to make them better. He quickly developed a reputation for building strong and light bicycle parts that were well worth their cost. Years later, Trek bought Bontrager and began incorporating Keith’s parts on its bikes. Today, most of Trek’s bikes are outfitted head to toe with Bontrager products.

Tech Features:

The Drop Line post from Bontrager is an internally routed dropper seatpost perfect for riders from many different disciplines. It comes with an ergonomic under-bar remote, or a rider can purchase an above-bar remote for $22 so that the post can be used with two- and three-ring drivetrains. The Drop Line is designed to fit into a seat tube with a 31.6-millimeter diameter and comes in three different travel options: 100, 125 (tested) and 150 millimeters. The post has a keyed chassis to prevent rotation and uses a two-bolt rocker head with micro adjustments so riders can easily dial in their saddle tilt. The Drop Line uses a cable to actuate its air-sprung hydraulic cartridge, which provides riders with infinite adjustability. Our test post weighed in at 412 grams, and sells for $300. You can purchase one at any Trek dealer.

M4Bontrager2Field Test Results:

Bontrager’s Drop Line comes ready to be installed with cable, housing and a remote that mounts under the handlebars. Riders with dual- or triple-ring setups will need to purchase Bontrager’s universal lever separately. Installing the post was fairly straightforward after we internally routed the housing through our frame. It’s important to note that not all bikes have routing for internal droppers, but if your bike is only a few years old, you are likely good to go. The Drop Line cable is actually routed backwards, meaning the cable is clamped at the remote instead of at the post. This design allows riders to easily remove and reinstall the post. Out on the trails, the post operated well in ideal conditions and warmer weather. Some of our test riders had issues on cold rides that resulted in the post not returning properly. Our test riders were happy with the return speed of the post and found that dialing in saddle tilt was easy. The Drop Line only comes in a 31.6-millimeter diameter, and riders with more than one chainring are forced to purchase an additional remote. But, if the post will work for your bike, then we think it’s a good option at a fair price.


• Multiple travel options to choose from
• Infinitely adjustable
• Lever has nice ergonomics


• Only available in a 31.6-millimeter seat tube diameter

• Does not return quickly on cold rides


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