Fox Factory Transfer SL. It is a spring with some sort of mechanical lock! Despite the box packaging that clearly states that it is a hydraulic post with infinite position adjustment.. it's two position only and fully mechanical. Anyways, last spring I had been reading up on the current crop of mechanical droppers and the various problems and issues that everything had so far. I was not very impressed with what was available and pretty much shelved the dropper idea. Then in June I saw that Fox had announced dropper post that they billed as a new super light XC oriented post. While they didn't make a big deal about how it was spring powered I saw it in the fine print and had a bit of a light bulb moment. It took three months of trying to get one of the dropper posts into my hands, my LBS wasn't able to get me one and eventually I found it in stock online two weeks ago. The post and lever is slightly heavier than the carbon Whisky seat post that came with my bike but it's not really a huge deal since my fat bike weights around 30lbs with an alloy frame and alloy wheels.
I went with the Kashima coated Factory version partially for the bling factor, but also because I think the Kashima coating may help keep the post working when it gets really cold. One would think for a $400 dropper post it would come with a freaking remote lever, cable, and housing but no, it did not. Decided to use a Wolftooth remote lever with the longer paddle as the Magura brake clamps on my bars were by my measurements, going to be in the same spot that I wanted the remote clamp on the standard lever length. The longer lever lets the clamp sit inboard of the Magura clamps. Also, I could get the Wolftooth remote lever in gold for a bit of matchy matchy style points. The actuation of the lever and the post is surprisingly light and the post itself does not take much force to drop. It's also pretty loud and really fast when extending! So far, at about 25* it's worked perfectly. But so has both of the Bontrager Line droppers we have on other bikes, although they move significantly slower in these temps.
I did a handful of changes to my fatbike over the summer that really have helped the overall feel of the bike. I swapped out the carbon fork the bike came with for the one I pulled off my wifes' Farley, mainly so I had a thruaxel that actually worked and didn't irritate me. Old one was a weird QR thruaxel with an easily lost insert on the threaded side, hated it with a passion. New fork has a regular DTswiss thruaxel that has way less moving and no removeable parts. It raised the front of the bike by about 10mm and slackened it to about 68* but since the steerer tube was shorter it lowered the bars overall . Swapped for a shorter stem and flipped it to bring the bars back up to about where they were. Then I added this dropper and a set of Magura MT8 SL brakes to replace the SRAM Level T brakes. With all of these changes it's really made the bike feel so much better. I'm excited for a set of brakes that actually work and has carbon levers so I don't frost bite my fingers again from using my brakes! That day sucked.. needed to use brakes but I could feel the bitter cold from the alloy levers through my gloves inside my poagies.