FSA has a brand new dropper post, one that replaces the previous model that we didn't have much luck with. Thankfully, it looks like FSA has addressed all of the issues that we had, as well as making improvements in other areas. The Flowtron takes its name after a fast, rolling flow trail near FSA's Pacific Northwest headquarters, and it will retail for $269 USD when it hits the shelves this coming January.
There will be two travel options, one with 150mm and the other with 125mm, and a new, lower profile head means that some riders who couldn't quite squeak the long-travel older post into their frame might now be able to get away with 150mm of stroke. Travel is controlled by a new alloy-walled cartridge (the old one was steel) with a 6mm shaft (the old one was 8mm) that helps to drop 90-grams from the design. Return speed is non-adjustable, with this being set by the charged cartridge.
One thing that is adjustable, however, is the force required at the completely redesigned thumb lever. This is tweaked by the wound return spring at the bottom of the post being set to one of three different positions, with the idea being that some riders like an ultra-light feel while others want a firmer push required at the lever. Adding return spring tension could also help overcome a bike's crappy cable routing that might add friction.
We've seen a few droppers employ some sort of linkage setup at the bottom of the post to depress the cartridge's plunger, but FSA has gone with a composite cam that accomplishes the same thing. Why composite? After testing this material against both steel and alloy cams, they found that the composite version showed the least wear by far, so there you have it.
The cable also mounts opposite to what was used on the Flowtron's predecessor, with its head fitting into a slot on the cam and being clamped by a hex screw up at the lever, something that should make getting the internally routed (sorry, no external option) housing cut to the correct length much easier. Internally, FSA has gone from two flat brass keys on the old dropper to using three round keys on the Flowtron, a change that is said to make for a much more robust design, and one that sees far less wiggle up at the head.
The new lever sits on a hinged clamp, and its textured thumb paddle is massive - there's no missing this thing.