Most of the headlines around the OneUp V3 are probably going to focus on how light it is. That sure is what OneUp has been leading with. They even wrote it on the box. Twice. Not saying I blame them. The claimed weight of the 150 mm V3 is actually less than that of the 150 mm Fox Transfer SL, which has only two fixed positions, and the letters “SL” in its name! The next perk to the V3 is that it’s got an even lower stack height and overall length than the V2, which already had the least wasted space of any dropper on the market. That’s a big deal. Back in my shop days, a lot of folks were just 5 mm short of bumping up to the next tier in dropper length. More than ever, OneUp posts will be the most broadly compatible (internally routed) option out there. Let’s see if I can put all the various configurations into a single, grammatically correct sentence: The V3 comes in a 90, 120, 150, 180, 210, and 240 mm version, (including a 27.2 mm diameter in the 90 and 120 mm models and 34.9 mm diameter in all but the 90 mm), each of which offering the capability to drop its travel internally by 10 or 20 mm.
But the most important perks to the V3 post aren’t as easy to quantify as its weight or length. OneUp’s new longevity features will probably matter a lot more to most of us. Literally starting from the top, OneUp is now using a dust wiper made by SKF, a storied Swedish brand who’s been in the low-friction biz for many decades. Same with Germany’s IGUS, who are now providing the bushings in the V3. Speaking of which, the 210 and 240-millimeter posts get increased bushing overlap, meaning the bushings are further apart for greater support and longer wear.
V3 (left) V2 (right)
OneUp also increased the number of pins that prevent the post from rotating, including two pins that are made of a slightly oversized polymer instead of brass like the rest of them. The “oversized” part makes for a tighter fit for less wobble, while the “polymer” part prevents that tighter fit from adding friction. This is great news, along with the changes to seals and bushings. The most common issues I’ve encountered with droppers arise from wear and tear between the upper and lower post. That’s the area that demands the most frequent attention in the form of disassembly, cleaning, and re-lubricating. But the second-most common issue is a failure in a dropper post’s actual dropping mechanism. In the vast majority of posts today, that mechanism is a cartridge. And the vast majority of cartridges are impenetrable black boxes. Unless you’ve got a hell of a lot of time on your hands (or a rebuildable Bike Yoke post and a reasonable amount of time on your hands), when the cartridge goes bad, you replace it. So, I had to see what the V3 cartridge looked like. And what I saw got me a little worried.
V3 (left) V2 (right)
It’s no surprise that every major component in the V3 dropper is lighter. The chassis, the saddle clamp, even the cable actuation doohickey (I know it’s called a bell crank) all shaved a few grams. But the largest single weight drop happened in the cartridge. It’s pretty crazy to hold the beating heart of the V3 dropper in your hand. It’s so light and so skinny. Although the post’s robust outer shell is providing lateral support, channeling your butt’s myriad forces in an arrow-straight line, the little pencil-thin rod inside is what holds up your weight. And the tiny seals it’s attached to are what prevent oil or air from leaking. And speaking of air, though the V2 cartridge was topped with a Schrader valve, the V3’s air chamber is permanently sealed. It all seemed a little fishy, but I decided to withhold judgment until I learned more about the cartridge. And boy, did I learn. I sent a few questions to Jon Staples, co-founder and CTO at OneUp, and instead of working his answers into entirely new prose, I’ll just CTRL+V them here.
The V2 cartridge is thicker. Am I missing something by thinking bigger is better?
The V2 was air filled and designed to run at pressures achievable by a standard shock pump. As such, the diameter needed to be large enough to get decent return speed and force from 300 psi. The OD of the V2 cartridge was also very close to the ID of the upper tube on V2 which limited the ID profiling that was possible. The V3 cartridge, in contrast, runs higher pressure and is factory nitrogen filled (more on that later). The higher pressure allows a smaller diameter piston to achieve our desired return speed and force as well as giving us more freedom to extend the top of the cartridge further into the upper tube (saves upper tube weight).
The new cartridge “body” is longer than the old one. Anything interesting to say about that? Like, does it bump up the air or oil volume lost with the narrower diameter?
The V2 cartridge was a twin tube system so it could be shorter and fatter but carried more oil and aluminum making it heavier. The V3 is longer because the nitrogen chamber is inline with the oil chamber. This saved significant cartridge weight but required the longer body (and required the body to extend further into the upper tube as noted above). This also allowed us to remove the IFP, making the cartridge fully self-bleeding.
Losing the ability to adjust pressure might be seen as a downgrade to some people. Why would you say it isn’t?
The single biggest source of a cartridge losing pressure comes from the Schrader valve itself, especially when running pressures at, or close to, 300 psi (as most droppers do). Air is also more prone to leak out than pure nitrogen. By removing the fill valve, filling with Nitrogen and removing any threaded end caps (threads can sometimes nick O-rings during assembly) we’ve designed a cartridge that never needs to be filled. On a side note, adjustable pressures may seem like a good idea but in reality 300 psi is typically just enough to make a post function properly with a 20 mm OD cartridge. Dropping to 240 or 250 psi runs a real risk of making the post lethargic and/or having it fail to top out.
I assume the V2 dropper was never technically intended to be user-rebuildable, but the V3 is definitely not. Did the V3 cartridge’s factory-sealed construction offer any benefits in regard to longevity?
100%. As noted above, the system is designed to maintain pressure for years. If it ever does require replacement the process takes five minutes using a 14 mm wrench, 5 mm hex and 2 mm hex (or an EDC tool). For the average customer that is a much more friendly undertaking than a rebuild that would take a qualified mechanic a few hours. The cartridge structure is also 98% pure aluminum, uses a relatively low volume of oil and can be rendered inert with our recommended puncturing procedure. Recycling instructions will be online and visible at the time of launch.
What, if anything, can you say about the design process behind the cartridge? Did many of the improvements originate at OneUp? Was it the result of back-and-forth with the cartridge manufacturer?
The cartridge is 100% designed at OneUp. Everything from the piston shape and valve design to the oil and nitrogen charge was developed over the course of 18 months to achieve exactly the performance we wanted. This is not the Wintec-style off-the-shelf-solution that is seen in many of our competitors.
Will the V3 cartridge eventually be on the site as a service part like previous cartridges? Do you have an MSRP?
Yes. It will be available at launch for $79.99 USD. All small parts and service kits for the V3 Dropper will be available at launch.
So, Jon had me at “nitrogen.” If I list all the chemical reasons why a nitrogen-filled air spring is more reliable than an air-filled one, I’ll never get to my damn ride impressions. But tell me this: How often have you needed to top off the nitrogen behind your suspension’s IFP? Most answers will range from “never” to “what’s an IFP?” If you want a dropper post that you can strip down to the O-rings and fix yourself, buy a Bike Yoke. They’re great posts. But they’re also between $80 and $140 more than the OneUp V3. It’s pretty impressive for a flagship dropper to go for $269.99 (299.99 with remote lever and cable) in 2024, when inflation has added a dose of sticker shock to nearly every new product release.That also comes with a two-year warranty, which should cover any failure in the cartridge if you’re still not convinced. And the cartridge is remarkably easy to remove. It took me about five minutes, which is a good thing ‘cause I didn’t get a bonus from The Radavist for doing this unnecessary surgery. My main job was to ride the thing and tell you how it works.
V3 (left) V2 (right)
To be fair, the best dropper reviews take between six months and a year to deliver real results. I had a week and a half with the V3. It’ll find a home on my big dumb enduro bike, so a potential long-term review will be on the spreadsheet for late in the year, but I still learned a lot on the handful of rides I managed to do. Most notably, I never thought about the ultra-light cartridge once the post was installed. Not sure what I expected, but the action is every bit as solid as any other brand new post I’ve used. And the return speed is pretty perfect. I’ve been dealing with slow posts lately. The OEM post on my Canyon Spectral needs a little TLC, and another dropper I’m testing has been a bit lethargic from the start. I won’t spoil which one, though. Just stay tuned.
As for when it’s moving in the other direction, the V3 cartridge is supposed to have lighter breakaway force than the V2. I didn’t have a brand new V2 for an apples-to-oranges comparison, but to what extent you’ll feel that lighter action depends on how good you are at not sideloading your post when compressing it. For me, it’s often a bit chaotic, and I might not always aim that full-body twerk in perfect alignment with the dropper post. The V3 still did get out of the way quickly and smoothly, but so would most other brand new high-quality posts. Not to keep repeating myself, but full results will require further testing.
And I won’t be the only one testing it. There will be a lot of these posts out in the wild. OneUp regularly shows up on audience-award lists, and they’re a popular choice for OEM spec. On that note, OneUp was acquired in 2022 by PON Holdings, a group that includes Cannondale, GT, Focus and Santa Cruz. But plenty of brands inside and outside of PON are speccing OneUp posts, and that number has been growing for years. Maybe that’s why they didn’t have to do anything drastic like go wireless. Maybe it’s enough to just keep getting better.
- Advanced, name-brand bushings and seals
- Improved bushing overlap in the longest posts
- Fortified anti-wobble components
- Nitrogen-charged return spring
- Impressive pricing for the package ($269.99 without remote lever, $299.99 with)
- Shorter overall length
- Lighter weight
- Not wireless
- No external air preload adjustment
- Die-hard DIY-ers can no longer service the cartridge (though very few ever did)
- Not wireless
See more at OneUp