Java NEO J Air Carbon EX12 16 inch Folding Bike
$7,800.00
Color Options
Grey Blue
Marbo Black
Oliver Green
Orange
Titanium Grey
White GreySize Options
The Java NEO J Air Carbon EX12 is the full-carbon 16-inch tri-fold bike in the Java NEO range: frame, fork, handlebar, stem and seatpost are carbon, paired with Wheeltop 12-speed electronic shifting (11–40T) and hydraulic disc brakes. Jollymap's review recorded about 8.35 kg with pedals. For riders who fold and carry every day, that is about 1.6 kg lighter than the aluminium-framed NEO 12s (about 10 kg) with the same electronic groupset, while keeping the same frame geometry as the aluminium 16-inch NEO.
Key Facts
- Category: 16-inch (ETRTO 349) full-carbon tri-fold folding bike, 12-speed electronic shifting
- Brand: Java (Shenzhen ChuangXinWei Bicycle Co., mainland China), official model NEO-349 CB
- Standout feature: T800 carbon main frame and T1000 carbon rear triangle, with steel reinforcement inside the folding joints; carbon fork, 6 cm mini M-bar, stem and seatpost
- Key numbers: about 8.35 kg with pedals (Jollymap review); Wheeltop 12-speed electronic, 11–40T cassette; 50T chainring, 165 mm cranks; hydraulic disc brakes
- Best for: riders who want a full-carbon 16-inch NEO in one go, plus electronic shifting and a 40T cog for Hong Kong's hills
The Problem It Solves
A folding bike gets carried up stairs, into car boots and onto MTR trains every day, and every kilogram counts. The aluminium NEO 9S standard weighs about 10.2 kg with pedals (Jollymap measured); the J Air EX12 brings that down to about 8.35 kg with a full-carbon frame and carbon bar, stem and seatpost. The carbon stem is left as bare carbon under a clear protective coat, saving the weight of paint. Frame geometry (wheelbase and BB height) matches the aluminium 16-inch version, so NEO owners who upgrade don't need to get used to a new position.
Who It Suits
- Good fit: daily folding commuters who care most about weight; riders who want push-button electronic shifting and a 40T cog for climbs; tinkerers planning carbon wheels or a double chainring later.
- Maybe not: if you're on a tighter budget or don't need electronic shifting, consider the aluminium-frame, carbon-fork Java NEO 9S 16 inch 349 9 Speeds Folding Bike (Carbon Fork version); for the same 12-speed electronic shifting on an aluminium frame, there is the Java NEO 12s 16 inch 349 Electric Shift 12 Speed Folding Bike (the same spec also comes in a limited polished-silver finish, the Java NEO 16" Folding Bike Chrome Limited Edition). Taller riders (for example over 180 cm) may prefer a 20-inch model, such as the Java NEO J Air Carbon 20 inch 12 Speed Folding Bike.
Key Features
Full-carbon frame with reinforced folding joints
The main frame uses T800 carbon and the rear triangle steps up to T1000 carbon for stiffness and torsional strength. Steel tubes are bonded inside the frame at the key folding points to strengthen the joints and improve durability.
Carbon handlebar, stem and seatpost
The 6 cm mini M-shaped carbon bar sits higher than the older 2 cm bar, saving many riders the cost of a riser upgrade. The seatpost has a matte upper section and a textured anti-slip band in the middle, so it holds its height once clamped.
Wheeltop 12-speed electronic shifting with a 40T cog
Twelve closely spaced gears make it easy to find a comfortable cadence, and shifting is a press of a button. The 40T largest cog (versus 32T on the older 9-speed) makes a real difference on Hong Kong's steep streets.
DECA full-CNC hydraulic disc brakes
Java's own DECA full-CNC levers and calipers, with red calipers. The fork dropout now uses a metal spacer that sets the front wheel back slightly, addressing earlier reports of the front wheel touching the crank.
Room to upgrade
New mounting holes on the chainstay let you fit a front derailleur with the Java Neo Front Derailleur Adapter for a double chainring. The stock wheels are aluminium; switching to carbon wheels such as the ODIN Tri-Spoke Carbon Wheelset for Java Neo or the Blast Wave Tri-Spoke Carbon Wheelset for Java Neo saves roughly another 200–300 g.
Java NEO Range Compared
Here is how the 14-inch, 16-inch and 20-inch Java NEO models compare:
| Model | Wheel size | Frame | Fork | Drivetrain | Weight (approx.) | Best for |
|---|---|---|---|---|---|---|
| Java NEO 14" 3s Folding Bike | 14" | Aluminium alloy | Aluminium alloy | 3-speed mechanical (Shimano, 11–17T) | 9.4 kg (Jollymap measured, with pedals) | Riders short of space at home, women, teenagers and short-trip commuters |
| Java NEO 14" Electric Shift 5-Speed Folding Bike | 14" | Aluminium alloy | Carbon fibre | 5-speed electronic (11–19T) | 8.9 kg (Jollymap measured, with pedals) | City riders who want a small 14" fold and electronic shifting |
| Java NEO 9S 16" 349 9-Speed Folding Bike | 16" (349) | Aluminium alloy | Aluminium alloy | 9-speed mechanical (L-TWOO shifter + Shimano rear derailleur, 11–32T) | 10.2 kg (Jollymap measured, with pedals) | First-time folding bike owners, weekend leisure rides and short trips |
| Java NEO 9S 16" 349 9-Speed Folding Bike (Carbon Fork) | 16" (349) | Aluminium alloy | Carbon fibre | 9-speed mechanical (L-TWOO shifter + Shimano rear derailleur, 11–32T) | 9.8 kg (Java official) | Riders who often ride for over an hour and want less vibration through the hands |
| Java NEO 12s 16" 349 Electric Shift 12-Speed Folding Bike | 16" (349) | Aluminium alloy | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) | 10 kg (Jollymap data); Purple Special Edition 9.6 kg (Jollymap measured, with pedals) | Riders who want electronic shifting and a wider gear range for hills |
| Java NEO 16" Folding Bike – Chrome Limited Edition | 16" (349) | Aluminium alloy | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) | — | Riders who want a 16" with electronic shifting in the limited chrome finish |
| Java NEO J Air Carbon EX12 16" Folding Bike (this page) | 16" (349) | Carbon fibre | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) | 8.35 kg (Jollymap measured, with pedals) | Weight-conscious riders who want a full-carbon frame |
| Java NEO 20" 9s Folding Bike | 20" (406) | Aluminium alloy | Aluminium alloy | 9-speed mechanical (Shimano CUES, 11–40T) | 10.2 kg (Java official) | Taller riders or long-distance cruisers who want the entry-level spec |
| Java NEO 20" 9-Speed Carbon Fork Folding Bike | 20" (406) | Aluminium alloy | Carbon fibre | 9-speed mechanical (Shimano CUES, 11–40T) | 10.5 kg (Jollymap measured, first-batch 20" carbon fork version) | Riders who want a 20" carbon fork bike with a wider gear range (up to 40T) for hills |
| Java NEO 20" Electric Shift 12-Speed Folding Bike | 20" (406) | Aluminium alloy | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) | 10.5 kg (Jollymap measured) | Taller riders or long-distance riders who want electronic shifting |
| Java NEO 20" Folding Bike – Chrome Limited Edition | 20" (406) | Aluminium alloy | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) or 9-speed mechanical (Shimano CUES, 11–40T) | — | Riders who want a 20" carbon fork bike in the limited chrome finish, with electronic or mechanical shifting |
| Java NEO J Air Carbon 20" 12-Speed Folding Bike | 20" (406) | Carbon fibre | Carbon fibre | 12-speed electronic (Wheeltop, 11–40T) | 8.9 kg (Jollymap measured, with pedals) | Riders who want 20" stability with a light full-carbon frame |
| Java NEO Carbon 20" 451 105 Di2 Folding Road Bike | 20" (451) | Carbon fibre | Carbon fibre | 2 × 12-speed electronic (Shimano 105 Di2, 52/36T, 11–34T) | 9.4 kg (Jollymap measured, with pedals and drop bar) | Riders who want road-bike position and speed for long rides and climbs, but need a bike that folds |
Sources: each model's Jollymap product page, Jollymap review articles and the Java website. Weights are measured differently, so treat them as a guide.
For a walk-through of the whole range, see Jollymap's article Java Neo folding bike family guide (in Chinese).
Jollymap's Advice
Shift into the lowest gear (largest cog) before folding a NEO to reduce chain drops, and push the folded bike forwards so the cranks don't turn and catch a pedal on the wheel. The stock saddle is firm; for longer rides consider the Air Seat 1 AFT Suspension Saddle, and for easier parking the Mr TiParts Carbon Kickstand for Java Neo 16 inch. Watch the torque on carbon parts. Before adding a front derailleur or new wheels, chat with us or message our Facebook page before ordering to confirm compatibility.
Specifications
| Java NEO J Air Carbon EX12 16" | Specification |
|---|---|
| Official model | Java NEO-349 CB |
| Frame | Carbon (T800 main frame, T1000 rear triangle) |
| Fork | Carbon |
| Seatpost | Carbon |
| Handlebar | Carbon, 6 cm mini M-bar |
| Crankset | 50T hollow 165mm aluminum alloy |
| Bottom bracket | Threaded |
| Shifter | Wheeltop electronic 12S |
| Derailleur | Wheeltop electronic 12S |
| Cassette | 11-40T 12S |
| Chain | 12S, 104 links |
| Brakes | Hydraulic disc brakes (Java DECA full-CNC levers and calipers) |
| Wheelset | 16-inch 349 aluminum alloy wheelset |
| Saddle | Black |
| Weight | About 8.35 kg with pedals (Jollymap review) |
| Colours (Jollymap) | Titanium Grey, Marbo Black, Grey Blue, White Grey, Oliver Green, Orange |
Specifications source: Java website (NEO-349 CB), Jollymap review articles and Jollymap product information.
Frame: 5-year warranty
Product Specifications and arrival date are subject to final confirmation by the factory.
FAQ
How much does the Java NEO Carbon 16-inch weigh?
About 8.35 kg with pedals, as recorded in Jollymap's review. Carbon wheels can save roughly another 200–300 g.
What is the difference between the J Air EX12 and the aluminium NEO 12s?
Frame and component materials. The J Air EX12 has a carbon frame, fork, handlebar, stem and seatpost and weighs about 8.35 kg with pedals; the Java NEO 12s 16 inch has an aluminium frame with a carbon fork and is listed at about 10 kg. Both use Wheeltop 12-speed electronic shifting, an 11–40T cassette, 50T 165 mm cranks and hydraulic disc brakes.
Is a carbon folding frame durable? Are the folding joints weaker?
Java bonds steel tubes inside the frame at the key folding points to strengthen the joints, and the T1000 carbon rear triangle keeps its strength even with slimmer tubes. When adjusting or replacing the carbon handlebar yourself, tighten bolts in a cross pattern and control the torque.
Is the riding position the same as the aluminium 16-inch NEO?
Yes. The carbon version has the same frame geometry (wheelbase and BB height) as the aluminium 16-inch NEO, so there's nothing new to get used to. The 6 cm mini M-bar sits a little higher than the 2 cm bar.
Can I take it on the MTR or a bus when folded?
Java has not published the folded size of the NEO-349 CB. For reference, the aluminium 16-inch NEO folds to 69 x 30.5 x 58 cm according to Java, about 157.5 cm in total, within the MTR's 170 cm total-dimension limit (no side over 130 cm). On franchised buses, the Public Bus Services Regulations (Cap. 230A) section 14 only allows free carriage of items within 5 kg and 0.1 m³, which a whole bike exceeds, so it is up to the bus company and driver; minibuses make no guarantee either.
Can I add a front derailleur for a double chainring?
Yes. The carbon version has new mounting holes on the chainstay, and the Java Neo Front Derailleur Adapter lets you fit a front derailleur for a double chainring. Drivetrain compatibility matters here, so contact us before ordering.
16-inch or 20-inch carbon NEO: which suits me?
Choose 16-inch if you fold onto the MTR often or have limited storage; choose 20-inch if you're tall (for example over 180 cm) or ride long distances. The 20-inch carbon model is the Java NEO J Air Carbon 20 inch 12 Speed Folding Bike, about 9 kg with pedals. Jollymap's article Java Neo 20 vs 16: what's different? (in Chinese) compares the two sizes in detail.
Can I fit a kickstand to the J Air EX12?
Yes, but it needs a J Air-specific stand. The bike has no kickstand from the factory, so parking means folding the rear wheel. The Mr TiParts Aluminum Kickstand for Java Neo J Air 16 inch (120 g) or the Mr TiParts Carbon Kickstand for Java Neo J Air 16 inch (102 g) mounts under the rear disc brake and does not affect folding. Kickstands for the aluminium-frame Java NEO do not fit.
Where can I buy the Java NEO Carbon 16-inch in Hong Kong?
Jollymap sells it online and in our shop, in Titanium Grey, Marbo Black, Grey Blue, White Grey, Oliver Green and Orange. Delivery dates and specification are subject to the factory's final decision, so chat with us to confirm before ordering.
Specifications and components follow the manufacturer's latest release and may change without notice. If in doubt, please contact us to confirm before ordering.
Last updated: October 2026
