Introduction to the L-Twoo Brand of Bicycle Gear Shifters in China
The mainstream bicycle gear shift brands with a high market share include three major ones: Japanese "Shimano," American "Sram," and Italian "Campagnolo." Currently, in the context of their rising prices and scarcity, whether purchasing complete bicycles, assembling or upgrading, all require a corresponding monetary cost. In this environment where unique products are available, it might be worthwhile to try out Chinese-made gear shift sets. In recent years, the development of gear shift sets from China has been rapid, and advancements in research and production technologies have transformed them from cheap and low-end "substitutes" to competitive products. After undergoing market challenges, an increasing number of bicycle manufacturers are starting to use them.
Starting from now, let's discuss Chinese-made gear shift sets, examining their appearance, usability, how to choose them, and providing informative advice for selection. This will enable cyclists to comprehensively understand these products.
Introduction of LTWOO, One of the Earliest Enterprises in China to Develop Gear Shift Sets
LTWOO, located in Zhuhai, Guangdong Province, is one of the earliest companies in China to develop gear shift sets. Founded in 2013, LTWOO, like several other domestic bicycle gear shift manufacturers, was founded by Liu Chunsheng, who had a background of working at SRAM. After starting his own business, LTWOO focused on the research and production of sport-level/civilian-level bicycle kits and gradually obtained OE orders from multiple domestic bicycle brands, becoming known to a wider range of cyclists. In addition to mountain bike kits with a considerable market share, LTWOO's independently developed road bike kits have also been launched for sale. They have even showcased electronic gear shift prototype products currently under development.
Mountain Biking
Road Bike
Folding Bikes
Combining LTWOO's latest product catalog for this year with configuration guides from some complete bike manufacturers, this article will categorize LTWOO's various kit products according to applicable bike types and explain them to readers.
Mountain Bike Section
LTWOO began with mountain bike kits, and their mountain bike gear shift kits are named the "A Series." The A Series enjoys a relatively high market share in the mountain bike market. Domestic manufacturers' adaptability is extraordinary. Despite the prevalence of 12-speed cassettes among major manufacturers, LTWOO introduced a 13-speed single-chainring mountain bike kit by optimizing the spacing of the large cassette, which is compatible with common cassette hubs without requiring additional changes. Based on different gear ratios, the mountain bike flagship products are A13/A12/A11. These products utilize the highest-grade materials and the most precise component processing among domestic kits, even comparable to racing-level finishes, exhibiting a cool and eye-catching style.
The A13/A12/A11 kits have the same structure and materials for the rear derailleur, even the weights are identical. Notably, the standout feature of these rear derailleurs is the use of a carbon fiber outer cage plate combined with oversized jockey wheels equipped with waterproof sealed bearings, offering both visual appeal and practicality.
The upper mounting bolt of the rear derailleur (the one connecting to the frame) is made of aluminum alloy and is anodized in the same color as the rest of the derailleur. Various parts of the derailleur are also hollowed out to reduce weight.
The main arm is lengthened to support a 52T large cassette, and the upper guide's eccentric design is offset.
Compared to SRAM's design, LTWOO has lowered the derailleur's height by 8mm, effectively avoiding collisions with the derailleur hanger and preventing damage.
A deeper analysis of LTWOO's rear derailleur reveals the influence of SRAM's design. The structure and cable routing of the main body are influenced by SRAM's non-clutched designs from earlier years. However, LTWOO has incorporated innovations and improvements. The carbon-legged A13/A12/A11 derailleurs are compatible with cassettes up to 52T, achieved through optimizing the length and angle of the main arm and the eccentric design of the upper jockey wheel. The optimized rear derailleur performs exceptionally well and prevents the common problem of derailleur hanger modifications causing issues with extreme-sized cassettes.
The "heirloom" high tension of SRAM is also evident in LTWOO's designs. The A13/A12/A11 kits utilize springs with higher tension than before, which can be quite stiff and hard to manipulate by hand. This is due to the absence of a clutch mechanism, necessitating increased spring tension to compensate. This results in a responsive and rapid shifting experience, both up and down the cassette. The rear derailleur's "shadow" structure is also optimized. While this structure was initially seen in SRAM's products during the 9-speed era, LTWOO has improved upon it, making the "shadow" effect of the derailleur more pronounced. After installation, it's even more discreet and secure than SRAM's newer models.
As for the shifters, there isn't much difference; in fact, LTWOO's entire series shares the same design. The only variation comes from the different gear ratios, leading to different shifting ramps. While the external design of these shifters resembles SRAM's windowless style, LTWOO has also conducted independent research and optimization. The earlier issue of excessive play in the shifts of larger SRAM shifters has been overcome, and the design of the cable slot's dust cover is more compact. LTWOO's shifters stand out for their crisp and precise feel, with rapid and distinct gear changes, aligning well with SRAM's American-style approach.
Moving down a tier, there's the AX series, which shares a basic structure with the flagship series. Other than a more subdued color scheme, the main difference is that the carbon fiber cage is replaced with a metal one. Nonetheless, there are still options for 13/12/11-speed ratios. In addition to the single-chainring kits that also support a 52T large cassette, there are now options for double-chainring and triple-chainring setups. Although an alternative front derailleur is available, the matching multi-chainring rear derailleur is a version with a different cage shape, supporting only up to 42/46T cassettes.
Among the users of the L-Twoo top-tier suite, there are not many issues encountered. The feedback received has been generally positive. However, L-Twoo's approach of using only a large coil spring to maintain tension on the derailleur arm to stabilize the chain is somewhat outdated. After all, rear derailleur damping systems are becoming more mature, with Shimano even incorporating derailleur arm damping into their latest 11/12-speed DEORE models. The reliability and durability of the large coil spring system are not as good as damping systems. However, L-Twoo's product positioning is aimed at high-end products that compete with mid-range offerings from major manufacturers at the same price point. Their target customers are not likely to use their products in extreme scenarios like downhill racing, and regular off-road riding is unlikely to wear out that large coil spring.
From A9 to A7, L-Twoo positions this series as mass-market, commonly found as original equipment on OEM vehicles, some even featuring the vehicle brand's logo. As you move from higher to lower numbers, manufacturers precisely reduce specifications, decrease gear ratios, and use lower-grade materials. For example, they may switch from metal to engineering plastics, use metal bushings instead of bearings in pulleys, and replace large screws with steel ones or cast iron. However, overall performance remains relatively consistent, with a more budget-friendly price point.
Regarding the front derailleurs, L-Twoo offers only two models: top swing and down swing, with a clamp-on specification. Typically, these are only seen on complete vehicles, regardless of the suite level. Across all suite levels, the front derailleurs are identical, differing only in paint finish.
Since both old and new versions of the rear derailleurs are available in the market, along with various colors and OEM versions, there's little difference in user experience. When making a purchase, pay attention to the length of the main arm below the large screw, as it indicates support for cassettes larger than 42T. Additionally, choose between mid-cage and long-cage versions based on your tooth capacity requirements.
Furthermore, the A-series products, A5, A3, and A2, designed for 9-speed or lower, are considered entry-level products, often seen on more affordable branded bicycles. To broaden adaptability and options, L-Twoo designed two cable pull ratios within this product range: one for compatibility with Shimano's 2:1 ratio and another for SRAM's 1:1 ratio. If you intend to purchase within this series, be sure to inquire about the cable pull ratio, as some versions may have it printed on the derailleur arm.
Old Model New Model
For the different cable pull ratio designs, L-Twoo primarily modified the cable entry point on the upper arm component, with all other structures remaining unchanged, allowing for interchangeable production components. This series offers a wide range of compatibility, and as such, it includes short, medium, and long cage options, making the short cage rear derailleur suitable for many small-wheel bicycle models. However, it's worth noting that both old and new versions of the rear derailleurs exist. The old version visually resembles the A7, inheriting its appearance from SRAM with more metal components and better craftsmanship, while the new version optimizes the cable routing mechanism, simplifies fixing screws, maintains a cleaner appearance, has a lighter weight but includes more plastic components. Additionally, the lower-end shifters now come with a windowed version and feature a push-pull double-thumb lever operation, similar to Shimano's lower-end shifters, making them user-friendly for entry-level cyclists, although the windowed version feels more plastic compared to the non-windowed version, lacking a premium feel.
User experiences have been shared by many riders, based on the latest AX 13-speed suite tested on bicycles. Here's a summary by the author:
Visual Design: 9/10 (Sharp and dynamic design with a lightweight aluminum screw and carbon fiber derailleur arm, very appealing.)
Handling: 10/10 (American-style, responsive, and excellent single-thumb operation, as always.)
Shifting Experience: 9/10 (While the spring tension is high, the absence of a damping system means it can't deliver ultimate chain stability in off-road situations.)
Additionally, the author also owns various versions of A7 and A3 shifters and rear derailleurs. For A7 and A5, many are custom-made for manufacturers and feature a wide range of color combinations. However, there are differences in materials used, including whether the main body is made of metal or engineering plastic, whether the screws are chrome-plated or cast iron, and even differences in surface finishes, such as precision baking or injection coloring. It's essential to pay attention to these details when making a purchase.
As for A3 and A2 rear derailleurs, they come in two cable pull ratios. The Shimano version can replace the original rear derailleur in some low-end Shimano 8 and 9-speed mountain bike suites, offering improved tension and shadow-type rear derailleur performance, which is quite practical.
In the field of mountain biking, L-Twoo has reached its peak. Hopefully, the manufacturer will continue to invest in research and development to create more innovative and advanced products, rather than relying on older designs.
Flat-Bar Road and Folding Bike Models
While L-Twoo separately categorizes the F-series, specially designed for folding bikes and flat-bar road bikes, it still adheres to the nested model logic. L-Twoo combines its inherited mountain bike shifters with short-cage mountain or road rear derailleurs and flat-bar or clamp-on front derailleurs to create the F-series. Why such a combination? It relates to the unique requirements of folding bikes. Folding bikes primarily use a pull-down cable actuation system for front derailleurs, with less emphasis on the shifters. For rear derailleurs, short cage models are often used to prevent interference with the ground when using small-diameter wheels.
Because the production volume of the F-series is relatively small, retail prices tend to be higher. To inform you quietly, the OEM gearsets for certain international brand bicycle models are manufactured by L-Twoo. This suggests that international manufacturers are beginning to accept Chinese-made derailleurs, increasing their market recognition.
Road Bike Models
As mentioned earlier, L-Twoo has a strong presence in the mountain bike gearset market, while their independently developed road bike gearsets were introduced relatively late. Two years ago, there was a preview at a bike show, but after an extended period of internal testing and rider feedback, the products were only fully unveiled at the Bicycle Industry Conference hosted by the China Bicycle Association at the end of 2020. The full suite was presented to the public. Given the competitive landscape with several established international road bike gearset manufacturers, Chinese manufacturers faced challenges in developing new products due to existing patent barriers. L-Twoo managed to create its road bike gearsets with its own unique features after much effort.
L-Twoo's road bike gearsets, known as the R-series, correspond to their mountain bike counterparts. The design language for the entire series is consistent, categorized based on gear ratios. Carbon fiber and aluminum lever options are available, with little difference in performance between different levels. In terms of design, L-Twoo's road shifters have drawn inspiration from Campagnolo (CP), providing a comfortable grip with a slight adaptation of the curve to better suit Asian riders' palms. The brake lever's curve and distance also provide a more ergonomic feel, making control easier. These characteristics align with CP's renowned ergonomic design and user-friendly operation.
All major road bike gearset manufacturers have patents protecting their shifting methods. L-Twoo has taken a unique approach, with a larger lever for upshifting located behind the brake lever. It offers an outward push design, aligning with hand force requirements and without interfering with handlebar operation. Downshifting is achieved through a small thumb button located on the inner side of the shifter, easily actuated with the thumb. By now, you may have noticed the similarity to Campagnolo's design. However, while the logic is similar to CP's, the implementation and appearance differ. Additionally, CP's characteristic rapid multiple upshift feature is not present on L-Twoo's shifters due to the smaller button size and differing mechanisms.
The manufacturer claims that its road rear derailleur is compatible with Shimano cable pull ratios. Structurally, it is straightforward and resembles Shimano's early 11-speed 5800/6800/9000 designs. This type of rear derailleur is known for its fast initial movement, quick gear changes, lightweight construction, but modest chain stability and limited compatibility with very large cassettes. L-Twoo likely chose this development route for its mature data accumulation, shorter development cycles, lower risks, and ease of mass production.
The road front derailleur is more promising, available in clamp-on and direct mount versions. It employs an extended cable pull arm design, which is similar to Shimano's early 11-speed designs. This design is well-established and works well, offering a light and smooth cable pull action. However, it lacks an inner nylon guard, which is a feature found in Shimano's latest R7/8/9000 road gearsets. Shimano has also updated its front derailleur to feature a side-swing design, making it even more ergonomic and user-friendly. To compete, L-Twoo will need to make additional improvements.
L-Twoo also offers a single-chainring gearset for Gravel and road off-road use, a logical move given that the cable actuation design is compatible with Shimano cable pull ratios. The main difference between this and L-Twoo's mountain bike rear derailleur is the modification of cable routing and cable anchor points to achieve a Shimano-compatible cable pull ratio. Integrating and improving already developed and mature products is a common practice among manufacturers and allows for complementing each other's strengths.
This concludes the introduction to road bike gearsets. Here's a summary based on the author's testing of the latest market-available RX/R9 11-speed gearsets:
THe last is Electronic gear
eRX Disc Carbon 2*12s Electronic Shift Groupset
No.：eRX Disc Carbon 2*12s
Weight：include break total:1.3kg
Colour: Black
Appearance Design: 9/10 (Designer's touch, all-black finish with stylish and dynamic accents.)
Handling Feel: 8.5/10 (Improved ergonomics for a better fit with Asian hands, though the upshift button feels slightly stiff.)
Shifting Experience: 8/10 (Traditional structure for road rear derailleur, with improved tension for precise shifting. Both front and rear shifting are less prone to chain drops but lack new technology.)
Where are the deductions? While the appearance is quite appealing, there is room for improvement in the details. The use of standard crosshead micro-adjustment screws and chrome-plated steel screws in the top-tier series can be seen as cost compromises. It would be even better if they were replaced with stainless steel screws or, better yet, black aluminum screws. Although the shifting logic is straightforward, the internal lever springs and ratchets are somewhat stiff. Especially, the small button for upshifting requires more force to activate.
Proactive manufacturers listen to consumers' feedback and work to improve their products.
In conclusion, there's room for improvement in L-Twoo's gearshifters. Despite their attractive appearance, attention to detail is needed. Standard crosshead micro-adjustment screws and chrome-plated steel screws on top-tier models could be upgraded to stainless steel or even black aluminum screws for improved quality. While the shifting logic is simple, the internal lever springs and ratchets are somewhat stiff, especially the small button for upshifting, which requires more force to engage.
Forward-thinking manufacturers listen to consumer feedback and work to improve their products.
