TranzX ED01 Dropper Post Review: A Closer Look at Wireless Performance

Wireless components are at the bleeding edge of mountain bike technology. While synonymous with SRAM’s AXS groupset, there are a handful of other brands who have thrown their hat into the ring, developing electronic dropper posts, shifters and suspension. TranzX is the latest to join the fray with their wireless seatpost, named the ED01. As an outspoken holdout to the entire idea of batteries on mountain bikes, I feel well placed to give this post an honest review; primarily though my ability to not be enamoured by the lack of a cable running from the dropper lever and down into my frame. 

Construction & Technology

Similar to the offerings available from Magura and Rockshox, this dropper relies on a top mounted battery to power a small motor which actuates an air cartridge within the post. The battery itself is novel to the ED01, and is shipped with a charger which is powered by a USB-C outlet. As the actuator for the post is top mounted and the air valve is located on the bottom of the post, making for quick and easy pressure checks and adjustments. The cartridge (and most of the other individual components) is available as a replacement part through KWT if required, and is easily replaceable when following the servicing manuals provided by TranzX. Similar to posts from OneUp and PNG, you can perform a quick dust wiper service by merely unscrewing it, cleaning the surfaces and dripping in some lube. 

The lever body runs off a CR2032 battery, which powers a bluetooth transmitter that sends signals to the post. The lever itself is plastic, and when actuated presses a small button that is retained by a spring. Lever feel is quite different to what I am used to, given there is no ‘throw’ as you would expect when pulling a cable. Instead, it feels more like the indicator in your car. That being, it is either “on” or “off”, with no in-between. 

As a combined set including batteries, the post and lever came in at just over 750 grams: compared to the Fox Transfer post and Shimano lever it replaced this is around 100 grams heavier. Negligible, yes, but I did expect a cable free dropper post system to at least weigh the same as the cable actuated system that came before it. TransX covers the ED01 with a 2 year warranty. 

Installation

This is where wireless componentry really starts to come into its own. Installing a new dropper post and internally routing the cable can be a tedious, near frustrating process for a mediocre mechanic such as myself. Guiding the cables through the ports, cutting them to length, ensuring there is enough tension for proper actuation—quite the process. The ED01 install on the other hand was an absolute breeze. After checking the air pressure was set to the recommended 300psi, all I needed to do was slap the post in my frame to the desired height, and then mount up the lever on my handlebars. Admittedly installing the seat was a little finicky, however I would put most of this down to it being my first time installing a seat on a post with this two bolt mounting type. Once everything was torqued to spec, I had to merely pair the post to the lever: a 30 second process which is confirmed by a green flashing light on the lever body. Within minutes, I had the ED01 installed on my bike and was ready to get out for a ride. 

On the Trail

I typically run my dropper posts with about as much cable tension as they can handle without self actuating, to ensure I can drop and raise them as quickly as is mechanically possible. Similarly, I also run them with as much air pressure as is recommended by the manufacturer to keep return speed as fast and as audible as it can be. In comparison, the actuation and return speed of the ED01 was a touch slower than I was used to, even at max pressure. The post also seemed to have a bit of lag when first actuating it at the beginning of a ride or after not using it for a while during a ride, both of which were minor niggles that I eventually learned to live with. 

No ‘knock’ can be heard when the post reaches full height, a likely side effect of the return speed and also something I missed from my mechanical posts during testing. These minor gripes aside, I found the ED01 very easy to live with. As you’d expect, it goes up and down with a level of smoothness which is comparable to other sealed cartridge units like the OneUp Dropper, but lacking in comparison to high-end mechanical posts such as the BikeYoke Revive. Lateral play was minimal and not noticeable on the bike, nor was there any vertical play in the post when sitting on it. The novelty of pressing a bar mounted lever and hearing a little “bleep bleep” of the motor actuating on the post did not and is yet to wear off, to the point where I am still riding around and blipping the lever to my hearts content just so I can listen to those funny little sounds. I also had no issues with water ingress when washing my bike post-ride. TranzX do recommend that you always keep the battery installed and avoid pressure-washing the post head directly to ensure no such issues occur. 

Value

This dropper post kit sits right in the middle ground of what your money can get you in either mechanical or electronic components. With a price tag of just under $1k, it offers fantastic value in comparison to the Rockshox Reverb AXS which comes in with a RRP of around $1500. While the Reverb does have better lever feel and a more robust post head, I would not say those advantages alone are worth an extra $500. Alternatively, you can get a OneUp Dropper post and lever for around $500, nearly half what the ED01 costs. In comparison, the OneUp has better actuation and return speed performance, but is cable actuated meaning installation and maintenance is more difficult. 

Our Take

The TranzX ED01 was a dependable companion during the few months I had it mounted up on my bike. For those who are set on investing in a wireless dropper post, it offers fantastic value in comparison to the market leading Rockshox Reverb AXS. Further to this, it is also going to be available in a 200mm drop variant through the end of 2024, a full 30mm more travel than what is available from Rockshox. That being said, it is still hundreds of dollars more expensive and heavier than cable actuated dropper posts with similar performance. The question lies within, how much value do you put on ease of install and a clutter free cockpit? 

Diameters: 30.9mm, 31.6mm (tested)

Travel: 150mm, 170mm (tested)

Weight: Post 690g, Lever 68g (including batteries) 

RRP: $999.95

Available Through: kwtimports.com.au