The new Funn UpDown dropper post is ‘self-healing’ and it even fixes itself on the trail

by Wil Barrett 0

Funn has had its Updown dropper post available for a couple of years now, but it has very recently introduced a brand new version that features internal cable routing and up to 150mm of travel.

Really though, and aside from the name, this new version shares nothing in common with Funn’s first generation Updown dropper post – this one is entirely new, and features a unique set of internals that apparently allows the post to ‘self-heal’ itself from that dreaded saggy suspension syndrome.

funn updown dropper post
The Funn Updown dropper is brand new and features a unique Twin Tube damper inside.

Funn has achieved this by using a Twin Tube design for the hydraulic cartridge inside the post. Like the majority of dropper posts out there, it features an Internal Floating Piston (IFP) that separates hydraulic oil from air inside the damper. However, during riding or storage, air bubbles can sometimes make their way past the IFP and into the damping fluid. If you flip the bike upside down, or hang it vertically by the front wheel and accidentally activate the dropper, air will go where it isn’t meant to go. Air can also creep past the IFP seal head if the post is flexed enough during riding, where the alloy walls and seals actually distort.

Once that happens, you no longer get a nice solid feel underneath the saddle, with the post turning into a pseudo-suspension seatpost. Normally when this happens with any other droppers (like the RockShox Reverb or KS LEV for example), the post needs to be pulled apart to have the damper bled, which is pretty damn annoying.

This is an issue that German brand BikeYoke set out to address with its Revive dropper post, which features a ‘Revive’ valve that the rider can operate with an external lever to bleed the post. We’ve reviewed one, and it works. However, Funn’s post is meant to do the same thing, but all by its clever self.

While we were at Eurobike, we grabbed Dom from Funn to give us a nifty demonstration on how it works – check out the video below.

If you’re still wondering how it all works, we’ve got a graphic below that shows what happens each time the dropper post is compressed by the rider. During compression, hydraulic oil inside the central tube is forced out through a valve, and into the outer tube. Under rebound, that oil is sucked back through the valve and into the central tube again.

funn updown dropper post
The Twin Tube design helps to push any trapped air bubbles out of the damper and back into the outer tube where it belongs.

If air does work its way into the central tube, the same thing happens under full compression – air bubbles are carried with the oil through the valve and into the outer tube. However, once the air bubbles are in the outer tube, they rise to the surface (thanks to ol’ mate gravity), where they assume their normal position. And once they’re back there and out of the main damper, your post is returned to its rock-solid state again. How clever is that?

funn updown dropper post
A twin-bolt saddle clamp offers a more secure connection for the saddle rails.

Aside from the new guts, the Updown dropper post also gets a redesigned head with a twin-bolt clamp, which is likely to be much more secure than the single-bolt version on the old post. The stanchion and clamp head are also forged from a single piece of alloy, making for a lighter and stronger structure.

The Funn Updown dropper locates the cable head at the CORRECT end. No fiddly grub screws at the bottom of the post here.
funn updown dropper post
There’s a new under-the-bar lever too.

There’s a new under-the-bar lever as well, which gets a nice textured alloy lever, and a bolt-on clamp that’ll work with SRAM disc brake levers if you want to go full MatchMaker style. The lever is compatible with every other cable-activated dropper post out there too, as you can run the cable around both ways. The lever will be available separately for $39 USD.

funn updown dropper post
Right now, Funn is only offering the Updown dropper with 125mm and 150mm travel.

Funn Updown Dropper Post Features

  • Fully redesigned with internal cable routing
  • 125mm & 150mm travel options
  • Infinitely adjustable
  • Sealed RCR hydraulic cartridge with Twin Tube design
  • Self-bleeding system for removing air from the IFP
  • User serviceable
  • Construction: AL7050 inner and outer tubes
  • Diameter: 30.9mm & 31.6mm
  • Claimed weights: 550g – 625g (plus 35g for the lever)
  • RRP: $279 USD (including remote)

As well as the Updown dropper post, Funn had a few other new bits on show at Eurobike, including some fresh flat pedals, redesigned Fantom wheels, and a new handlebar and stem;

funn flat pedal
The Python flat pedals are made with CNC machined 6061 alloy and roll on a chromoly axle with “self-lubricating bearings”, which we’re guessing means bushings.
funn flat pedal
These pedals are super thin – 11mm is the claimed thickness of the Python’s platform.
handlebar funn stem trickstuff
Funn also has a new riser bar called the Full On, which will be available in two widths, including an 810mm option. There’s a also a new Crossfire stem that’s forged rather than CNC machined. Price starts at $65 USD for the stem, and an impressive $49 USD for the bars.
funn fantom wheels
Available in 27.5in and 29in sizes, the Fantom wheelset gets anodized alloy rims and a fast-engaging freehub.
funn fantom wheels
Rim width grows to 35mm (internal), making these ideally suited to the latest crop of 2.5-2.6in tyres.
funn fantom wheels hub freehub pawls
The 6-pawl freehub mechanism now has a black cap that sits over the top of the pawls and springs, so small parts don’t fly everywhere if you pull the freehub body off for service.
funn fantom wheels hub freehub
You get 102 points of engagement out of the Fantom’s rear hub – that is super fast!

Leave a Reply