Dahon K One Super Light 20inch 451 18speed Folding Bike FDA083
$4,580.00
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The Dahon K-One double-chainring version (FDA083) is a 20-inch folding bike with 451 wheels, 18 speeds (2x9), an aluminium frame and disc brakes, a hollow 53/39T double chainring, and weighs 11.95 kg with pedals. It brings a road-bike-style double chainring to a 20-inch folder for riders who want to go faster and further on a folding bike.
Key highlights
- Category: 20-inch (451) folding bike, 18-speed, disc brakes
- Brand: Dahon, K-One double-chainring version, model FDA083
- Key figures: Aluminium frame; 11.95 kg with pedals; hollow 53/39T double chainring; Wellgo folding pedals
- Gearing: 2x9, 18 speeds; Dahon Hong Kong notes that recent batches use Shimano Sora 18-speed shifters and derailleurs
- Best for: Riders on mostly flat routes who want a folding bike for commuting and longer weekend rides; if you mainly need short hops or a lighter, more compact folder, consider a 14- or 16-inch model
Why choose an 18-speed double-chainring folder?
The K-One double-chainring version pairs a 53/39T double chainring with a 9-speed cassette for 18 gears: use the 53T ring to hold speed on the flat, then drop to the 39T ring for climbs. That lets one folding bike cover both commuting and longer weekend routes, such as the cycle track from Sha Tin to Tai Po.
Who is it for?
The K-One double-chainring version suits riders with some experience who want to ride further or faster on a folding bike. If you mainly use a folder to reach the MTR or for short trips, the lighter Dahon K3 14-inch 3-Speed Folding Bike KAA433 (7.9 kg without pedals) or the Dahon K3 Plus 349 16-inch 9-Speed Folding Bike will be easier to carry. For a simpler single-chainring 20-inch folder, compare the Dahon Launch D8 (KBA083) 8-speed disc folding bike.
451 wheels
"20-inch" covers two tyre standards, 451 and 406 (the number is the rim's bead seat diameter in mm). The K-One double-chainring version uses 451 wheels, so replacement tyres must be 451 size (for example 20 x 1 1/8); 406 tyres will not fit a 451 rim.
Wellgo folding pedals
It comes with Wellgo folding pedals, which fold in when you store the bike.
Dahon 20-inch folding bike comparison
Here is how the Dahon 20-inch folding bike range compares, listed from fewest to most gears:
| Model | Wheel size | Drivetrain | Brakes | Frame | Weight (approx.) | Folded size (L × W × H) | Best for |
|---|---|---|---|---|---|---|---|
| Dahon Dream D6 20 inch Folding Bike HAT061 | 20" | 6-speed | V-brakes (Dahon global site, archived) | High-carbon steel | 14.3 kg (Dahon official) | 80 × 28 × 65 cm | First-time folding bike riders, 150–180 cm tall |
| Dahon Dream D6 20 inch Folding Bike HAT060 | 20" | 6-speed | V-brakes (Dahon global site, archived) | High-carbon steel | 14.3 kg (Dahon official) | 80 × 28 × 65 cm | Riders 150–180 cm tall and up to 105 kg |
| Dahon KBA061 Super Light 20" Folding Bike | 20" | 6-speed (14–28T) | V-brakes (Dahon global site) | Aluminium alloy | 12.06 kg (Dahon official) | 82 × 35 × 66 cm | Everyday riding, mostly on flat routes |
| Dahon SUV D6 20inch Folding Bike HAA061 | 20" | 6-speed (14–28T) | V-brakes (Dahon global site) | Aluminium alloy | 13.1 kg (Dahon Hong Kong, archived) | 80 × 34.5 × 66.5 cm (Dahon Hong Kong, archived) | Leisure rides on city streets or along the waterfront |
| Dahon Boardwalk D7 20inch Folding Bike HAC072 | 20" | 7-speed | V-brakes (Dahon official product photo) | Chromoly steel | 11.9 kg (Dahon official) | — | Leisure riders who like a retro look and the comfort of a steel frame |
| Dahon ROUTE 7Speed Folding Bike PYA071 | 20" | 7-speed (Shimano Tourney rear derailleur) | V-brakes (Dahon UK site) | Aluminium alloy | 11.98 kg (Dahon UK site) | 80 × 34 × 66 cm (Dahon UK site) | Riders 145–190 cm tall for exercise, short tours or shopping trips |
| Dahon 40 Anniversary Speed P8 20inch Folding Bike KBC083 | 20" | 8-speed | V-brakes (Jollymap product data) | Chromoly steel | 12.8 kg (Dahon official) | 81 × 31 × 66 cm | Riders 150–180 cm tall who want the 40th-anniversary paint and a simple V-brake setup |
| Dahon Speed P8 20inch 8 speed Folding Bike KBC083 | 20" | 8-speed | V-brakes (Jollymap article) | Chromoly steel | 12.7 kg (Dahon official) | 81 × 31 × 66.5 cm | Riders 150–180 cm tall who want a simple V-brake setup |
| Dahon Launch 2000 20inch Folding Bike KAC082 | 20" | 8-speed | — | Chromoly steel | 12.5 kg (Dahon Hong Kong, archived) | 76 × 37 × 66.5 cm (Jollymap product data) | Riders 150–180 cm tall for leisure and city riding |
| Dahon Launch D8 (KBA083) 8 speed disc folding Bike (Jaws Hinge) | 20" | 8-speed (Dahon custom rear derailleur, 11–32T) | Disc brakes | Aluminium alloy; Jaws folding hinge | 12.1 kg (Dahon global site) | 82 × 39 × 62 cm (Dahon global site) | Riders who want a firmly locking hinge and disc brakes |
| Dahon Launch D8 (KBA083) 8 speed disc folding Bike | 20" | 8-speed (Dahon custom) | Disc brakes | Aluminium alloy; standard folding hinge | 12.1 kg (Dahon official) | 82 × 38 × 64 cm | Riders who want an aluminium frame with 8-speed gearing, disc brakes and the standard hinge |
| Dahon K One 20inch Folding Bike FKA091 | 20" | 9-speed (11–32T) | Disc brakes | Aluminium alloy | 12.08 kg (Dahon official) | 87 × 41 × 67 cm | Leisure and fitness riders about 145–195 cm tall (Jollymap article) |
| Dahon Vigor D9 9 Speed 20inch Folding Bike - ECA093 | 20" | 9-speed (53T, 11–32T) | Mechanical disc brakes (160 mm rotors front and rear) | Aluminium alloy frame and fork | 12.68 kg (Jollymap review, with pedals and kickstand) | 79 × 37 × 67 cm | Heavier riders, or anyone who wants a stiff frame and a solid ride feel |
| Dahon KAA014 20inch Folding Bike | 20" | 11-speed | V-brakes (Dahon official product photo) | Aluminium alloy | 10.8 kg (Dahon official) | 81 × 39 × 65 cm | Experienced riders who are more demanding about gearing |
| Dahon K One Super Light 20inch 451 18speed Folding Bike FDA083 (this page) | 20" (451) | 18-speed (53/39T double chainring) | Disc brakes | Aluminium alloy | 11.95 kg (Dahon official, with pedals) | — | Riders who want 451 wheels and a double chainring for a wider gear range |
Comparison table sources: Dahon HK official product pages (dahon.com.hk); other sources are marked in the table. "—" means Dahon has not published the figure. Weights may not be measured the same way (for example, with or without pedals), so use them as a guide only.
Choose by what you need:
- The single-chainring K One: Dahon K One 20inch Folding Bike FKA091 — 9-speed (11–32T), disc brakes, aluminium frame, about 12.08kg according to Dahon, folding to 87 x 41 x 67cm.
- Simpler single-chainring 8-speed: Dahon Launch D8 (KBA083) 8 speed disc folding Bike — 8-speed with disc brakes and an aluminium frame, 12.1kg according to Dahon; also available as a Jaws hinge version.
- A stiff frame: Dahon Vigor D9 9 Speed 20inch Folding Bike - ECA093 — 9-speed (53T, 11–32T), mechanical disc brakes with 160mm rotors front and rear, 12.68kg with pedals and kickstand in our review.
Further reading: Jollymap article 2026 DAHON Folding Bike Buying Guide.
Jollymap's advice
An 18-speed double chainring gives you more gear choices, but you operate both front and rear shifting; if you just want simple gearing, the single-chainring Launch D8 may suit you better. Not sure this bike fits your routes and storage space? Chat with us or message our Facebook page before ordering, with your height, usual routes and where you will store the bike.
Specifications
| Brand / model | Dahon K-One double-chainring version, FDA083 |
| Wheel size | 20-inch, 451 wheels |
| Drivetrain | 18-speed (2x9); recent batches use Shimano Sora 18-speed shifters and derailleurs |
| Chainring | Hollow 53/39T double chainring |
| Brakes | Disc |
| Frame | Aluminium |
| Weight | 11.95 kg (with pedals) |
| Pedals | Wellgo folding pedals |
| Colours (Jollymap) | Black, Green |
Specification source: Dahon Hong Kong official product page (dahon.com.hk), DAHON K ONE double-chainring version (FDA083). Measurements may vary slightly due to different measuring tools; pictures are for reference only, please refer to the actual product.
*Components and parts may vary in different production batches. Enquiry is welcome.
FAQ
How much does the Dahon K-One double-chainring version weigh?
11.95 kg with pedals, as published by Dahon Hong Kong. Actual weight can vary slightly by batch and measuring tool.
What are the Dahon K-One FDA083 specs?
20-inch 451 wheels, aluminium frame, 18 speeds (53/39T double chainring with a 9-speed cassette), disc brakes and Wellgo folding pedals. Dahon Hong Kong notes that recent batches use Shimano Sora 18-speed shifters and derailleurs; parts can vary by batch, so please check with us before ordering.
What is the difference between the K-One FDA083 and the K-One FKA091?
The FDA083 has a double chainring with 18 speeds and 451 wheels, and weighs 11.95 kg with pedals. The K-One FKA091 is 9-speed, weighs about 12.08 kg and folds to L 87 x H 67 x W 41 cm. Both are 20-inch with an aluminium frame and disc brakes.
What is the difference between 451 and 406 wheels? Can I swap tyres?
No, the tyres are not interchangeable. Both are called 20-inch, but the rim diameters differ: 451 rims take tyres usually marked 20 x 1 1/8 or 20 x 1 3/8, while 406 rims take tyres marked 20 x 1.5 to 20 x 2.125. A tyre only fits when its bead seat diameter matches the rim, so the K-One double-chainring version needs 451 tyres.
How does the K-One double-chainring version compare with the K3 Plus?
The K-One double-chainring version is 20-inch with 451 wheels and 18 speeds, weighing 11.95 kg with pedals, and leans towards speed and longer rides. The K3 Plus 349 is 16-inch with 349 wheels, 9 speeds and disc brakes, weighs about 10.44 kg and folds to L 72 x W 39 x H 63 cm, so it is easier to carry up stairs and onto public transport.
Can I take the K-One double-chainring version on the MTR?
It depends on the folded size, which Dahon has not published for this model. According to the Transport Department, MTR luggage must not exceed 170 cm in total length, width and height, with no side over 130 cm; if a folded bike does not comply, you may remove the front wheel to meet the rule. Franchised buses are limited by section 14 of the Public Bus Services Regulations (Cap. 230A): free luggage is capped at 5 kg and 0.1 cubic metres, which a folding bike usually exceeds.
What is the maximum load and recommended rider height?
Dahon Hong Kong does not publish a maximum load or rider height range for the FDA083. If you are near the usual limits for a folding bike, please contact us before ordering.
Where can I buy the Dahon K-One in Hong Kong?
It is available from the Jollymap online shop and store, in Black and Green. To check the parts on the current batch, chat with us online or message our Facebook page.
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
