Bikes up to 60% offWe monitor over 40,000 bikes daily to find the best prices
Today’s Deals2025 woom
OFF AIR 4
A 20″ aluminum frame mountain youth bike with promax hydraulic disc brakes.
Compare the full range
Manufacturer Price
$1,249| Weight | 21.7 lbs |
|---|---|
| Frame | Aluminum |
| Suspension | Hardtail, 60mm |
| Fork | RST SPEX |
| Wheels | 20″ Aluminum |
| Brakes | Promax Hydraulic Disc |
Summary
The woom OFF mountain youth bike is praised for its lightweight design and kid-specific geometry, which enhances stability and confidence on trails. It features tubeless-ready wheels, hydraulic brakes, and dropper post compatibility, making it versatile for young riders. While it excels in handling and comfort, some reviews note minor issues with component compatibility and setup.
Lightweight design
Kid-specific geometry for stability and confidence
Tubeless-ready wheels and tires
Hydraulic brakes
Dropper post compatibility
Lacks a rear derailleur protector
Not setup tubeless from the factory
Component compatibility issues with other brands
The matte copper color makes the link between mountain biking and nature in a big way.
BikerumorEvery time I've ever had my kid on a Woom bike the thing that comes to the forefront is the stability and ease of control.
Cycling NewsIt’s an outstanding climber and a joy to ride on the downhill as well
Two Wheeling TotsFeedback?
View all reviews
Jul 2025 · Natalie Martins
Discover the woom OFF and OFF AIR, the kids mountain bikes that transform timid riders into confident trail enthusiasts.
Jul 2023 · Jordan Villella
The new version of the Woom OFF and OFF Air kid's mountain bikes get lighter, and a few new features to make them more capable than ever!
Jul 2023 · Josh Ross
A real bike for real riders who just happen to be small
Tubeless ready wheels and tyres
Hydraulic brakes
Dropper post compatible
Lightweight frame
Age appropriate gearing
Upright, stable geometry
Lacks a rear derailleur protector
Chainstay protector peels in heat
Setting seat angle is a hassle
Not setup tubeless from the factory
| Frame | Frame material: lightweight, high-quality 6061-T6 aluminum with butted and hydroformed tubes, 20″ wheels, Easy-access low top tube to assist dismounting, Long wheelbase and low center of gravity to aid balancing, Featuring woom-specific molded chainstay protector Colors: Cirrus Cloud; Terra Coppa; Black |
|---|---|
| Fork | RST SPEX hydraulic air suspension fork with 60 mm travel, adjustable compression, and rebound damping, plus lock-out, 1 – 1 ⅛″ tapered steerer tube, 100 x 15 mm thru axle, Post mount for disc brake Travel: 60mm Spring Type: Air |
| Headset | Fully integrated 1 – 1 ⅛" headset, Sealed industrial bearings |
| Stem | Forged aluminum, CNC-machined, Handlebars attached via two clamps, Rise/drop: +/-15° with flip-flop design to adjust the handlebar height, Length: 50 mm |
| Handlebar | Wide, ergonomically adapted and lightweight aluminum bars for more control, Tapered end to fit a child’s hand, Sandblasted and silver anodized, Width: 570 mm, Rise: 20 mm |
| Saddle | Ergonomically designed to fit a child’s anatomy, Streamlined, mountain-bike-specific saddle design, Side protection to lean against walls |
| Seatpost | 27.2 x 250 mm, Anodized aluminum seatpost with insertion marks that indicate the minimum insertion depth, Quick-release seatpost clamp Type: Rigid |
| Grips | Child-friendly because of a small diameter, Single-clamp grip to prevent twisting, Safety zone: extra rubber on the palm-facing portion of the grip for added comfort, 100% silicone for maximum grip |
| Brakes | Hydraulic disc brakes by Promax, Rotor diameter front/back: 140/140 mm, Ergonomic brake levers designed for a child’s hands Type: Promax Hydraulic Disc |
|---|
| Rims | Tubeless-compatible Alexrims wheelset, Aluminum hubs with sealed industrial bearings, Thru axles for maximum torsional strength (100 x 15 mm front and 135 x 12 mm rear), 20 G14 spokes, double-crossed spoking, Aluminum nipples |
|---|---|
| Tires | 20 x 2.25″ Schwalbe Rocket Ron with ADDIX SPEED rubber compound, Quality mountain bike tires with low rolling resistance, maximum grip, good shock absorption, and excellent durability, Presta valves, tubeless conversion ready |
First added August 9
Last updated May 30