Is 34.9mm The Next Major Standard? BikeYoke Adds Huge Revive Max Dropper Post

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BikeYoke, the maker of that slippery-smooth Revive dropper post, has just sent us information about a new, bigger version of the Revive. Called the Revive Max (we’ll save you the shouting by writing it without capitals), this dropper post is purpose built for an emerging trend of 34.9mm diameter seat tubes.

Scott used to use a 34.9mm diameter seat tubes for the superlight Scale hardtail and Spark full suspension race bikes, but it was mostly for weight purposes, not for running a dropper. More recently, GT has made use of 34.9mm seat tubes on its Force model, while Liteville has elected for an oversized seat tube in order to offer the Eightpins integrated dropper post system, citing the bigger diameter 34.9mm diameter could offer up more space inside to fit in a durable and strong mechanism that can offer more overall drop.

A much newer and more mainstream bike that is also using a 34.9mm diameter seatpost is the 2017 and 2018 Specialized Enduro. The reason behind this move is that Specialized is making its own 34.9mm dropper post called the Command WU. We actually reviewed the WU dropper last week, and while its unique tilting action is novel, we couldn’t help but wonder if Specialized could have just made a regular dropper post with more travel.

Well, looks like BikeYoke has beaten them to the punch.

bikeyoke revive dropper post 34.9
The 34.9mm diameter Revive Max will fit 2017 & 2018 Specialized Enduro models.

Well, technically the RockShox Reverb has beaten BikeYoke to the punch. The Reverb is already available in a 34.9mm diameter and with up to 170mm of travel. However, BikeYoke has gone one further with its design, offering up to a huge 185mm of travel!

Designed for 34.9mm frames, the Revive Max obviously features a larger diameter for the main outer tube. But BikeYoke says it is unique in that it features a proportionally bigger stanchion (28mm diameter on Revive Max vs 25mm on the standard Revive posts), which means not only is it stiffer and stronger, there’s also more room for all the guts inside.

The punt that BikeYoke is taking, is that Specialized is likely to filter the 34.9mm diameter seatpost throughout its range, potentially with the next Stumpjumper model. And if Specialized do that, other bike companies are likely to take even more notice. Dropper posts are great tools, and more frame designers are electing to use shorter seat tubes so that they can fit longer travel dropper posts. But that can put a lot of stress on both the dropper and the frame. A larger diameter seat tube however, frees up the ability to build a stronger, stiffer and more robust dropper post while still getting that extra long stroke.

As for the post itself? Well we haven’t used one yet – it’s brand new. We tested and reviewed the BikeYoke Revive dropper post last year, and were particularly impressed with its uber smooth action and low overall stack height. The post did have a bit of an issue with the Revive function, though we’ve been assured has been sorted on the second generation. We’ll be getting one of the new 185mm travel Revive droppers in soon for testing, so stay tuned for that review.

bikeyoke revive dropper post 34.9
The design is shared with the existing dropper – including the unique revive function.

In the meantime, here’s the entire press release from BikeYoke;

World´s first dedicated 34.9 dropper post with up to 185mm drop

Why bother with a shim-adapted dropper post in a high end frame like the new Specialized Enduro, EVIL Wreckoning, Pyga Hyrax or Slakline, Liteville and the likes?

One should not forget, that many more bikes with 34.9mm seat tubes are not unlikely to come, since – yes, undoubtedly – especially E-Bikes with more critical requirements in terms of legal testing reports will greatly benefit from the strength gain.

Until now there was no dedicated 34.9 dropper post available, that had various travel options with up to 185mm of travel. While there have been some brands with 34.9 options, all of them based on their regular sized siblings with original upper tube diameter. Means: Those droppers just used a bigger lower tube and kept the general design unchanged.

More space inside the seat tube comes along with huge possibilities to make the post stronger, stiffer, smoother, but other post designs fail to take advantage of those circumstances. However, the biggest design flaw – in our opinion – is, that those small/regular upper tubes would not really want to match with the oversized seat tubes. A bike of this price range deserves a properly designed and looking post. Period.

To be fair: There is one dedicated 34.9 post with an oversized upper tube, Specialized´s newest creation. However, this post only offers 115mm of tube travel.

BikeYoke now proudly presents the world´s first dedicated 34.9 dropper post, which was solely and completely designed for the oversized seat tubes.

bikeyoke revive dropper post 34.9
The 34.9mm option will feature a bigger upper tube too.

REVIVE MAX features a 28mm stanchion (original REVIVE 25mm), optimized wall thicknesses, increased bushing strength, while keeping the market´s shortest stack height and extremely low overall length/ travel ratio as it is already featured by its smaller REVIVE siblings. This minimizes the weight penalty to less than 50g, compared to a (160/31.6), resulting in a total weight of 590g for the post only, which is still lower than many competitors with less travel and smaller diameter. One should not forget, that the added weight is even less, considering, there is no more need for an extra shim inside the seat tube.

Of course, all REVIVE MAX will come with the latest revision of our patented instant reset function, and integrated quick-reset lever.

bikeyoke revive dropper post 34.9
The Triggy under-bar lever.

Post weights

  • 125/34.9: 530g
  • 160/34.9: 590g
  • 185/34.9: 630g

MSRP (including Triggy remote)

  • 125/34.9: $455 USD
  • 160/34.9: $479 USD
  • 185/34.9: $499 USD

REVIVE MAX will start shipping by middle of March to our dealers and distributors and end consumers.

For more information, head to the BikeYoke website.

Comments (12)

    A superb dropper, the best around with yet another new and utterly, utterly pointless new standard that offers at best zero performance gains.

    longer, stiffer more reliable sealing ?

    Perhaps Specialised could make the seatpost tube 50mm diameter and shim them down to 34.9.

    That way when they inevitably “innovate” (=increase the size) a new 35.9mm standard and so on we won’t all have to buy new frames 🙂

    Its perfectly good at 185/31.6 so you have to question why anyone would want to move up to this new size… that said, if you have something like a fully integrated 8pins post then you start to see why…

    Liteville were using the 34.9mm seat post size years before the 8Pins dropper post was ever thought of.
    In fact, I think they’ve always used that size?

    @Andy R – You’re absolutely spot-on there sir! Liteville has been running 34.9mm for some time, long before the Eightpins dropper post concept.

    I think there are have been a few other odd frames here and there that have run 34.9mm in the past, including Scott and GT. I thought Trek had one on the 2009 Top Fuel with the dinky seatmast thing, but turns out it was actually a 34mm diameter :-/

    ST Wil.

    It’s like we’re living through an ice age of innovation, with each step so incrementally small, we’ll be slowly widening our bikes over decades to come.

    My Reverb is fine, don’t even know what size it is, but it goes up and down really well

    andybrad “longer, stiffer more reliable sealing ?”

    Longer:they already do a 185mm dropper, which I own, it’s fantastic. So it’s not longer.
    Stiffer:Do you really believe that the diameter of a seatpost that is a few mm wider but made of the exact same thickness metal will make any noticable difference whatsoever? You don’t even sit on the wider part with a dropper and why would anyone want the most uncomfortable part of their bike to be even more uncomfortable (stiffer)?
    More reliable sealing:Really? The seals are more realiable because the diameter of the post is wider?

    I own the Revive 185mm, it’s superb, totally reliable and very well made which is good.

    Introducing pointless new standards with marginal to zero gains every two minutes to force people to buy new stuff is bad. Sadly that’s how the MTB industry has always run itself, fine, as long as people realise that there are ZERO gains from slightly widening a seatpost etc.

    @duir: Sacki from BikeYoke speaking here:
    First of all, I am not a fan of new standards. Not at all! But this is not a new standard. It has been there for more than a decade and now it makes sense more than ever before and i´ll explain why, but first I want to address the pints above:

    1. Longer: We didn´t claim it was longer, but other manufacturers will want to make longer droppers as well, and they will greatly benefit from bigger diameters
    2. Stiffer: The difference between 25mm and 28mm is more than noticeable. It is not stiffer in a way of being more uncomfortable, but the flex is drastically reduced, which allows smoother movement under load – for example, when you don´t move your butt directly in posts direction.
    3. More reliable seals: not neccessarily seals, but a dropper seatpost can be a highly complicated unit (especially if it is not based on our REVIVE design). There are multiple tubes and pistons and IFP invloved. That takes a lot of space and engineers and happy to get every 10th of a millimieter of build space. Remember that brand that offered 150mm droppers in 30.9 and 31.6 and then suddenly, the 30.9 disappeared while the 31.6 remained? You would say it is only 0.7mm in diameter, right? Those 0.7mm were enough to make the difference.

    PRO 34.9:
    1. A post can be designed a lot stronger with around same weight or little wieght penatly. Now you would believe, that there are no issues with current strengths of droppers, right? You need to consider it globally and out of the box. E-Bikes have higher safety standards and they need stable droppers, also because it is more likely that heavier people are riding those bikes.
    2. Posts can get more travel while keeping same at same strenght. With the current 31.6 diameters we have reached a limit, where is is extremely expensive or heavy or impossible to generate more drop. In any case it is extremely difficult. I am not saying we need more drop than 200mm. But it would be possible with 34.9 posts.
    I would really appreciated it, if the industry could settle for one diameter, especially it is totally nonsense to have 31.6 AND 30.9. 34.9 makes a lot of sense to me nowadays with all the foresight in the e-bike market. But then again: For XC Racers, 34.9 might be too stiff. They are still on their 27.2s. Now make an educated guess, why there are no droppers (or just a handful) in 27.2.

    glad to hear, that you are happy with our REVIVE. 😉

    KS have done a 34.9mm size for yonks – and in a 175mm drop

    9point8 does 200mm and works flawless. AND comes in today’s standard diameters.

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