OneUp V3 Dropper Post
Lengths Available: 90 mm, 120 mm, 150 mm, 180 mm, 210 mm, 240 mm
Diameters Available: 27.2 mm (90mm and 120 mm drop only), 30.9 mm, 31.6 mm, 34.9 mm
Blister’s Measured Weights:
- 240 x 31.6 mm post: 614 g
- 22.2 mm clamp remote: 48 g
MSRP:
- Seatpost: $269.99 USD / $364.99 CAD / €291.99 / £291.99
- Remote: $44.99 USD / $59.99 CAD / €49.99 / £44.99
- Seatpost + Remote: $299.99 USD / $399.99 CAD / €324.99 / £320.99
Intro
We’ve been big fans of the OneUp V2 dropper post for quite a while now. It comes in a huge range of sizes (including a 240mm-drop version that’s longer than anything else we’re aware of); it’s relatively affordable; it’s among the shortest posts out there in terms of both stack height and total length per amount of drop; it’s relatively light; and we’ve had great luck with the durability across a whole bunch of them that we’ve used over the years.
Even though the V2 post was still a great option in today’s market, OneUp saw room for improvement. And their new V3 post looks to keep just about everything that made the V2 great, including the same size options and travel adjustability, but in a package that’s now even shorter and a substantial amount lighter. So how have they gone about it, and what’s changed on the new V3 Dropper? Let’s take a look.
Design
OneUp clearly understood they had a good thing going with the V2 post. They’ve tried to refine it where they could, rather than trying something completely different for the V3, and most of the high-level details and features have remained the same.
The V3 Dropper is still available in the same lengths (90–240 mm of drop, in 30 mm increments), all of which can still be reduced in travel by 10 or 20 mm by installing brass pins under the collar. It’s still cable-actuated, infinitely adjustable within the travel range, and uses the same routing scheme as the V2, with the same bushing for the cable end and a quick-release disconnect for the cable at the end of the seatpost. The cable still routes in the correct (in my opinion, anyway) direction, with its head at the end of the seatpost, the post attaches via a functionally identical two-bolt seat clamp, and so on.
But OneUp has given the internals of the V3 dropper a big overhaul, with three main goals: to make the new post lighter, smoother, and more reliable. And they’ve managed to trim a little bit more length out of the post while they were at it, too. That gives the V3 dropper both the shortest stack height (i.e., height from the bottom of the collar to the seat rails with the post lowered) and the shortest total length per amount of drop of any currently available seatpost that we’re aware of. The V3 dropper’s stack height is now 30 mm for the smaller diameters and 25 mm for the 34.9 mm version, and the total length is now 295 mm for the 90 mm post up through 610 mm for the 240 mm one (with the intermediate sizes coming in at 350, 415, 480, and 545 mm).
On the smoothness front, the V3 post now uses self-lubricating IGUS bushings with increased overlap to reduce friction, and posts with 180 mm drop and up get a third bushing to better support the longer post. The collar gets an upgraded SKF seal to help keep out dirt, and a new collar with that updated seal is now also available for V2 posts. The V3 post now uses six guide pins (up from three on the V2 post), two of which are an oversized polymer version to help reduce the amount of side-to-side play in the post. OneUp says the improved seals and bushings allow for longer service intervals, with a basic “clean and grease” recommended at 120 hours, and a full rebuild at 350. The V3 post can be fully disassembled with just a 14 mm wrench and 2 and 5 mm Allen wrenches (all of which are featured on the OneUp multi-tool) in just a few minutes.
The V3 dropper still uses a sealed, replaceable cartridge for its actuation, but that cartridge has also been redesigned to save weight and reduce friction. OneUp says it requires a massive 75% less breakaway force to start moving than the V2 cartridge and is smoother throughout its travel as well. Interestingly, the air pressure for the return spring on the V3 cartridge is no longer user-adjustable and is now sealed from the factory, along with the hydraulic inner workings. I’ve rarely needed to top up the V2 post, and the V3 cartridge might well be better sealed since it forgoes an external valve, but it’ll be interesting to see how that aspect of the V3 post holds up in the long term.
OneUp says that the V3 post is, in total, about 60 to 70 grams lighter than the V2, with most of those savings coming from the cartridge itself. We don’t currently have identical versions of the V2 and V3 posts on hand to compare weights, but our 240mm-drop, 31.6mm-diameter V3 post weighs 614 g; that’s within a reasonable tolerance of OneUp’s stated 610 g and is 33 grams lighter than a 240mm-drop, 30.9mm-diameter V2 post. Given that OneUp says that the 30.9 mm post saves about 25 grams as compared to the larger 31.6 mm version, that claim sounds about right.
The V3 cartridge itself is 43 grams lighter than the V2 one but isn’t backward compatible with the older post. The rest of the weight savings come from redesigned clamp parts, a new actuator at the bottom of the post, and other minor tweaks. A titanium bolt kit (which works on both the V2 and V3 posts) is also available separately and saves a claimed 10 grams. OneUp says that the V3 post is now the lightest infinitely-adjustable post on the market at any given travel, and is even a touch lighter than the two-position-only Fox Transfer SL.
[The V3 post’s new actuator also features a slightly deeper recess for the housing ferrule to sit in, making it more secure when working out the housing length and installing the post. It’s a subtle but welcome refinement that makes the V3 post just a tiny bit easier to install than the V2 one.]
OneUp’s V3 Remote has been on the market for a while now and carries over to the V3 post. It’s similar to the longstanding V2 remote that preceded it, but with a rubber thumb pad for increased grip and a cam on the cable-pull mechanism to increase leverage and decrease the amount of force needed to get the lever moving. The V3 Remote is available in a whole bunch of colors and with either 22.2 or 31.8 mm bar clamps (the latter being designed to run near the stem on drop-bar bikes), or with direct-mount configurations from SRAM (Matchmaker X) and Shimano (I-Spec EV and I-Spec II).
OneUp offers a two-year warranty on the V3 Dropper and says that spare parts will be available for V2 posts for at least another five years.
Some Questions / Things We’re Curious About
(1) The updates that OneUp has made to their V3 post sound great on paper (and it’s definitely lighter and smoother out of the box than the V2). But how do the service intervals shake out in practice, and does the V3 post really stay tight with less play for longer? We’ll just need to log a lot more time on one to find out.
(2) Does the non-adjustable air spring in the new cartridge feel like a limitation, or does it hold air well enough that it doesn’t matter?
Bottom Line (For Now)
We were already big fans of the OneUp V2 Dropper, and the changes they’ve made to the V3 make it even more appealing on paper. We’ve got a V3 Dropper in for testing and it’s working great so far — and is indeed noticeably smoother than the V2 post. So it seems like OneUp has a winner on their hands, so long as the V3’s long-term durability hasn’t suffered. We’ll log a lot more time on the V3 Dropper in the months to come and report back on how it fares.
I’m curious if the 34.9 upper post is the same diameter as the smaller post sizes?
ie is it designed to take advantage of 34.9 or built for 30.9 and shimmed out?