
Teardown | First Impressions
FSA FLOWTRON Dropper Post Teardown
FLOWTRON
Full Speed Ahead (FSA) is taking a stab at the why-spend-more 150mm dropper post market with their well named FLOWTRON post. Wearing the increasingly-common 250 USD price tag, it includes a nice feeling remote, a solid looking three-keyway chassis with a one-piece shaft/head unit, 3-way adjustable cable leverage, and (quelle surprise!) a Wintek cartridge.

I've had the Beastie Boys rhyming "three keyways it's got no play || it be getting down with no delay" in my head for days.
Whether it's the X-Fusion Manic, new Bontrager Line, or Crankbrothers Highline I'm talking about I've had great results with dropper posts #poweredbywintek and all those examples have pros and cons that make them easy to recommend in different situations.
From my first impression tearing this post down with Jeff I'll be adding it to the list, especially since the slightly strange looking remote feels great.

There it is in black and white. The new FSA FLOWTRON 150mm dropper.
Over the years FSA has earned a reputation for manufacturing quality, excellent customer service, and solid warranty commitment. Aluminum cranksets aren't in the same league as droppers when it comes to assembly QA but having seen the inside of this post, I'd say FSA is up to the task.
As disassembly goes FLOWTRON is a tight package that requires some elbow grease. A vice is definitely helpful but a competent home mechanic will be able to tackle this without issue; no proprietary tools required.
Cartridge
There is vast variation between Wintek-driven posts and trying one won't give you much idea about the others. I'm personally a fan of a couple of non-Wintek designs, but when it comes to performance and longevity at the lowest possible price, Wintek is what I recommend.

Here comes the full monty

Mmmm yeah, showing some bare metal

Wait a second

Oh, hey Wintek... fancy seeing you here
Out of the box the FLOWTRON has a nice tight head unit with no play, thanks to three easily replaced brass keyways, and a medium return speed from the cartridge that I think the vast majority of riders would be happy* with.
*If you want a faster return you won't be buying a Wintek cartridge post

The Wintek cartridge is held in place at the head with a nut.

And at the bottom by the actuator.
The cartridge is not rebuildable, but a readily available replacement is 50 USD when the time comes. Based on my experience with other posts, that will be hundreds of hours of riding with the only service required being a re-lubing of the main seal, easily accomplished without even removing the post from the bike.
That Remote
The FLOWTRON's remote was not an aesthetic love-at-first-sight experience for me but the ergonomics are great and thanks to the adjustable cam on the post it has the light action I prefer. It will also make riders who prefer more positive resistance from their dropper remote happy. The shape seems to mate well with the few brake levers I've bolted it against and once installed it looks much better.

The FLOWTRON's remote looks a bit different but the ergonomics, smooth motion, large ridged paddle, and hinged clamp are all on point.
This remote appears to be a solid winner in the 250 USD class. I'll still give the slight performance leg up to the TRS+ with its cartridge bearing but the FLOWTRON's lever is much simpler and lower profile.

I hooked the FSA remote up to Jeff's Banana Bike for a laugh but it's doing duty on my 2019 Kona Honzo ST.

The remote works great on the inside of brakes with short lever blades (Magura HC here) if you have long thumbs or outside with a long-levered brake like the TRP if you have short thumbs.
Adjustable Actuator
Thanks to three spring positions on the cam at the bottom of FLOWTRON, once the post is removed it's quick and easy to adjust the lever actuation from a very light feel to a more positive push. Access to that range without having to buy different remote levers, is something even much more expensive posts don't offer.

The three spring positions on the cam correspond with three different feels at the remote lever.
Full Speed Ahead

Over-forkers and owners of unfashionably slack seat tube angle bikes rejoice!

The Flowtron's lower seat clamp is reversible which helps slam that saddle forward.
FLOWTRON arrived nicely greased inside and very well assembled and the total teardown, including pausing for photos, took about fifteen minutes. A full clean of a dirty post including new seals and keyways is going to take significantly longer but a service on this FSA dropper, like other Wintek posts, should cost a fraction of the total for a service on a post with an IFP like the Reverb. Even if it's time to recycle the old cartridge the total is going to come out below the routine service on more complicated droppers.

Thumbs Up! A strap wrench, socket and adjustable wrench are all that's needed to teardown the Flowtron - but a vice with soft jaws sure is handy.
Now it's time to see if the FSA FLOWTRON lives up to its potential. I'm going to make it go up-and-down-and-down-and-up all winter in the worst conditions the North Shore has to offer and then I'll report back.
Any questions? Please post a comment below or check out the FLOWTRON at FSA.
Comments
kekoa
5 years ago
Any article with a 'Right Said Fred' and Beasties reference is awesome!
Reply
Andrew Major
5 years ago
Stoked someone appreciated it (other than me). Thanks!
Reply
DanL
5 years ago
It's the Right Said Fred one that really sets the bar
Reply
Nouseforaname
5 years ago
Do we really need any more dropper post reviews at this point? Note to manufacturers - if you're not making one by this point - don't bother. Put that effort into something new that isn't one more drop into a fully saturated market.
Reply
Andrew Major
5 years ago
On the one hand lots of folks still seem to be interested in reading them - so yes.
On the other hand I get plenty of messages from riders either replacing a sh*t post that came OE on their bike or looking at the bill to service their Reverb (or to change the remote from the plunger) asking questions that reference these teardowns - so yes.
Cheers,
Reply
Andy Eunson
5 years ago
Yes we do. The more competitive the market the better off we are.
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