Shimano 105 di2 Killer? L-TWOO eRX Groupset First Look

Shimano 105 di2 Killer? L-TWOO eRX Groupset First Look


L-TWOO is a Chinese company that focused on bike shifting components. (category link) Last year, they launched the first Chinese-made hydraulic groupset for road bikes, and now they are about to release an all-new electronic hydraulic groupset.

The All New L-TWOO eRX

-What is “eRX”

The eRX (product page link) is L-TWOO’s new 2*12 speed electronic hydraulic shifting system. It is a series of products born from L-TWOO’s accumulated development experience in the field of road bike hydraulic brakes, combined with electronic transmission technology. Essentially, it is an electronic version of the earlier RX series, as you can tell from its name – they simply added an “E” for electronic at the beginning of its name.

The eRX is made of many high-end materials, such as carbon fiber and aviation-grade aluminum, which provide the rider with an extremely precise control experience.

-How it works?

The eRX system uses a semi-wireless program, similar to the latest Shimano Di2 system. It utilizes wireless communication transmission technology to connect and pair the shifters with the derailleurs, and the shifters are powered by replaceable batteries.

There is a 14500 850mAh lithium seatpost battery to provide power to the front & rear derailleurs. And to charge this battery, all you need to do is plug in the magnetic charging cable to the rear derailleur.

-Product List

Just like the RX series, L-TWOO did not provide drivetrain components with the eRX system, giving customers more flexibility to choose third-party components for better performance or to save money. (Check Cybrei drivetrain components)


The eRX shifter features a modular cylinder structure, which makes it easier to produce and less prone to failure. Additionally, L-TWOO has developed an ergonomic design with a slimmer grip area, making riders feel more comfortable when holding the shifters.

The function of the shifter buttons can be set through L-TWOO’s own app. Equipped with carbon fiber levers, the weight of the eRX shifter is reduced to 225 grams on each side.

–Front Derailleur

The eRX front derailleur may appear simple, but it is highly efficient. One major difference from the mechanical RX derailleur is that it does not have limit screws. In this brand-new electronic derailleur, each half gear can be adjusted independently. The high and low limits, as well as the moving stroke parameters, can also be adjusted through the app.

The structure of the derailleur plate has been optimized, greatly improving shifting efficiency. It can automatically adjust its position to be compatible with the chain line, preventing any annoying noises when cross-chaining.

The eRX front derailleur has a maximum 16 tooth capacity (max difference between largest and smallest rings). And it weights 136 grams.

–Rear Derailleur

L-TWOO is using an integrated main unit inside the eRX rear derailleur. It adopts the Standby electronically controlled sleep system, which saves more power. This system reduces the response time of the derailleur to 22 milliseconds, making it extremely fast!

The seat tube battery can be charged through the rear derailleur, using a magnetic USB charging cable and a power bank. This makes charging more convenient.

The eRX rear derailleur also has a unique mechanical disconnection structure that automatically disconnects the rear derailleur and motor in the event of a strong collision, making it safer. It also resets automatically after the collision.

The eRX rear derailleur is made of carbon fiber, aviation aluminum, and other materials, making it lighter and more durable. The official weight of the eRX rear derailleur is 270 grams, and it is compatible with cassettes up to 32T.

–Seatpost Battery

L-TWOO’s seatpost battery uses a 14500 lithium battery with super-long battery life, capable of supporting over 3000 kilometers of riding after being fully charged. The battery comes with a magnetic USB charging cable, which starts charging as soon as you touch the cable to the rear derailleur.

 The official weight of an eRX battery is 62 grams.

–The all new L-TWOO APP

You can easily use Bluetooth to connect your eRX system with the L-TWOO APP on your phone. The APP supports functions such as controlling shifting, setting buttons, fine-tuning the chain line angle, and checking the status of the derailleurs. Half gears and high & low limits can also be adjusted easily within the APP.

-What is the price

The price of the whole eRX system is 4499 RMB (654 USD), which includes shifters, two calipers, front & rear derailleurs, seatpost battery, and cables.

Still too expensive? L-TWOO also brings us a more reasonable priced version – eR9, which uses aluminum to replace carbon fiber parts to make it cheaper. The eR9 groupset costs 3499 RMB(509 USD)

-Weight Comparison

Product Weights (grams)

Shifters+Calipers 807 640 733 814 749 822 845
Front Derailleur 136 96 116 142 167* 176* 180*
Rear Derailleur 277 215 262 302 299* 326* 366*
Battery & Cables 90 68 68 68
System Weight 1319 1019 1179 1326 1215 1324 1391


L-TWOO provides a full range of accident solutions for e-series products, covering product damage and natural wear and tear caused by various reasons including collision-caused damage, motor failure, wear damage, etc. L-TWOO provides a two-year full-free warranty service for non-human damage situations. For e-series products that are over two years old, L-TWOO provides paid maintenance and warranty services.


L-TWOO’s eRX groupset is a big step forward for Chinese shifting components. It’s great to see a brand that was once known for making low-end components now able to compete head-to-head with the big brands that have monopolized the industry for a long time.

L-TWOO is a new competitor in the electronic groupset market, which is currently dominated by Shimano and SRAM. The use of high-end materials and wireless technology could attract some cyclists who are looking for an alternative to the well-known brands. The modular cylinder structure of the shifters and the lack of limit screws in the front derailleur are interesting features. However, it remains to be seen how the groupset will perform in real-world conditions and how it will be received by cyclists. The price of the eRX system is lower than the Shimano 105 Di2, which could make it a viable option for budget-conscious riders who want to try out electronic shifting.

We hope L-TWOO can keep pushing and make more “people’s groupset”. That is what every cyclist would love to see.

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Comments (9)

  • Martin Smith

    I’m very keen to buy the eRX electronic groupset, but despite visiting the LTWOO official page at various times since the release, it doesn’t appear to be on sale yet. Any news on when it will be available?

    May 7, 2023 at 2:11 am
    • Tom Zeng

      We are looking at July, when it becomes more reliable and stabilized. (the first and second batches usually come with problems and we don’t want this to happen in our website, so let’s give them some to make their products 100% complete)

      Anyway, subscribe to our newsletter and we will let you know when they available!

      May 7, 2023 at 11:23 am
      • Martin John Smith

        Thanks Tom. That makes perfect sense. I remember Joe saying this before about the store policy for new products. Looking forward to picking up a groupset later this year.

        May 7, 2023 at 6:42 pm
  • Carsten

    I’m looking forward to some more competition in the electronic groupset market (let’s face it, yes the development cost were probably substantial, but in the long run they are likely simpler and hence cheaper to manufacture than similar mechanical groupsets, so the prices are ludicrous).
    I’m pretty disappointed that L-Twoo stopped at 32 teeth, though. Given that every other current electronic groupset (be it from Shimano, Sram or Campa) can handle at least 34 teeth cassettes.

    May 7, 2023 at 10:07 pm
  • Tony Bolton

    Hi there. Do you know if a gravel version of this is in the works? And if it is roughly when it might become available? Thanks

    May 8, 2023 at 8:59 am
    • Tom Zeng

      Unfortunately, we haven’t heard about any news about the electronic gravel groupset yet. Since their hyudraulic technology is getting more and more mature, hope they will make some electronic gravel groupset someday.

      May 10, 2023 at 2:29 am
  • hebon2

    I ordered it from the Aliexpress ltwoo shop and for now, having shifting issues, battery issues, and app issues. It does seem to be made well so its probably my fault or something I’m doing wrong but later today ill be taking it to a local bike shop to look at it im hoping they can sort some things out because I think this groupset could be awesome 🙂

    June 30, 2023 at 2:14 pm
    • Joe Whittingham

      Yeah, we’re not selling it yet because we’re not 100% confident in it. I (Joe) am also having some issues with mine (waterproofing.) Will update with a video at some point.

      July 1, 2023 at 12:50 pm
  • bemoturbo666

    I have put Shimano Ultegra 12-speed cassette with 11-34 tooth. And it is working okay. Although we have to spend a lot of time trimming the gears. Is it because we forced it to use 11-34? Will setting up for 11-32 be much easier?

    July 20, 2023 at 2:42 am

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