woom OFF AIR 4
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The ultralight and durable 20″ mountain bike with front suspension, 9 gears and disc brakes designed for children aged 6 years and over.
Welcome to the world of flow!
The next-generation woom OFF AIR 4 is an ultralight, durable hardtail mountain bike with serious all-terrain capabilities for kids aged six and up. With high-quality front suspension and powerful disc brakes, it teams maximum comfort with full control for the ultimate performance on XC trails, gravel tracks, tarmacked lanes and beyond.
Frame
- Frame material: lightweight, high-quality 6061 T6 aluminum with butted and hydroformed tubes
- 20″ wheels
- Confidence-inspiring handling: an easy-access low top tube, low centre of gravity and long wheelbase provide good balance and make for a fun, safe ride
- Hard-wearing plastic chainstay protector prevents scratches
Gears
- 9-speed gearing
- SRAM X5 trigger shifter
- SRAM X5 rear derailleur
Fork
- Aluminum air-sprung suspension fork from RST
- Rebound and compression damping adjustment, plus lockout function
- 60 mm travel
- 1 1/8″ – 1″ baby taper steerer tube
- 100 x 15 mm thru-axle
- Post mount for disc brake
Wheels
- Lightweight, tubeless-ready aluminum rims from Alexrims
- Size: 20″
- Aluminum hubs with sealed industrial bearings
- Thru-axles for maximum torsional strength (100 x 15 mm front / 135 x 12 mm rear)
- 20 spokes, double-crossed spoking
- Aluminum nipples
Headset
- Fully integrated 1 1/8″ – 1″ headset
- Sealed industrial-grade bearings
Tires
- 20 x 2.25" Schwalbe Rocket Ron
- with ADDIX SPEED rubber compound and Tubeless Easy technology
- Tubeless-ready
- Presta valves
Stem
- Forged aluminum
- CNC-machined
- Handlebars attached via two clamps
- +/-15° flip-flop design to adjust handlebar height
- Length: 50 mm
Saddle
- MTB-specific saddle
- Trail-ready design
- Ergonomic and age-appropriate design to fit the rider's pelvis
- Side protection to lean against walls
Handlebars
- Wide, lightweight aluminum bars with tapered ends
- Width: 570 mm
- Rise: 20 mm
Seatpost
- 27.2 x 250 mm
- Anodised aluminum seatpost with insertion marks that indicate the minimum insertion depth
Grips
- Child-friendly thanks to small diameter
- Ultra comfortable with reinforced contact surface for palms
- 100% silicone for maximum grip
- Clamped design to eliminate twisting
Seatpost clamp
- Quick-release aluminum seatpost clamp
- Extra-long quick-release lever, easy to operate requiring minimal strength
- No risk of turning and/or twisting
Drivetrain
- Lightweight forged aluminum cranks
- 110 mm length, narrow Q-factor
- Narrow-wide chainring with 28 teeth
- Cassette with 11–32 teeth
- Platform pedals made from fiber-reinforced nylon with metal pins for added grip
- Cr-Mo axle and sealed industrial-grade ball bearings
Brakes
- Hydraulic disc brakes by Promax
- Disc diameter (front/back): 160/140 mm
- Ergonomic brake levers designed for children's hands
Included tools
- 4 mm hex key for stem
- 8 mm hex key for front wheel and pedals
Weight
- 9.2 kg (without pedals)
Weight limit
50 kg (maximum combined weight of bicycle, rider and cargo)
Colors
- black
- terra coppa
Shipping dimensions
112 x 64 x 23 cm
Your OFF-road adventure can begin shortly!
Watch this video to find out how to assemble your woom OFF AIR, which tools you need, and how to set up the front suspension to suit your child.
Find more information in our Service & Info area.
Our woom bikes don't come with any additional accessories. You need to add optional extras like kickstands and mudguards on our equipment page.
If your child plans on cycling on public roads and streets, their bike may need to meet certain standard requirements before it can be considered legal in your country of residence. In many countries, bikes must be equipped with a bike bell, front and rear lights, and wide-angle Z reflectors. As rules for cyclists and their equipment vary from country to country, find out about the regulations applicable to riding a woom bike in road traffic in your country or region, particularly regarding the use of lights, reflectors and other obligatory safety equipment.
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Superlight Frame
The superlight aluminum frame has capable off-road geometry with a long wheelbase and slack head angle for improved stability and smooth, responsive handling. Extra confidence comes from the kink in the top tube, which makes it easy to dismount quickly in any situation.
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Premium suspension fork
Comfort and control on the bumpiest terrain is a given thanks to the fully tunable suspension fork, which can be adjusted to the rider’s weight. With adjustable compression and rebound damping, the fork can be tuned precisely for any terrain or conditions and features a lock-out function that basically switches off the suspension when not needed – meaning full fun on the trails and a faster ride up hills or on the way home!
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Ergonomic contact points
The age-appropriate MTB saddle and ergonomically profiled handlebar grips add comfort, while the hard-wearing platform pedals with metal pins provide the necessary grip for all-terrain riding.
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Precise shifting
The precise and intuitive SRAM X5 drivetrain has nine gears and a wide gear range thanks to the 28-tooth chainring up front and an 11–32 cassette at the rear. The easy-to-operate trigger shifter operates smoothly and reliably to make light work for children’s thumbs.
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Reliable disc brakes
Easy-to-modulate disc brakes are teamed with child-specific, reach-adjustable brake levers to provide maximum stopping power and control in every situation including steep slopes and wet conditions.
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Grippy tubeless-ready MTB tires
High-quality Schwalbe mountain bike tires combine low rolling resistance with superior grip and proven durability. With Tubeless Easy technology and tubeless-ready rims, it’s a straightforward transition to go tubeless and benefit from added comfort and grip.
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Lightweight flip-flop stem
Specially developed from forged aluminum, this stem pairs the ultimate stiffness with the lowest possible weight. Thanks to its flip-flop design, there’s the option to raise the height of the bars simply by inverting it.
Our standard 2-year warranty applies to the frame and components automatically from the day you purchase your woom bike. Members of our woom Riders Club can extend the warranty on aluminum frames, rigid forks, handlebars, stems and cranks to 10 years for free by registering their bike within 9 weeks of buying it.
Click here to join the woom Riders Club.
Click here to find out more about our extended warranty and to read the full terms and conditions.
assembly