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woom OFF AIR 4

Lightweight Aluminum Frame
Suspension Fork
Gears
Innovative Braking System
High-Quality Tires
Ergonomic Contact Points
Easily Adjustable
1/8
woom OFF AIR 4

The ultralight and durable 20″ mountain bike with front suspension, 9 gears and disc brakes designed for children aged 6 years and over.

In stock & delivered in 2-3 business days
OFFOFF AIR
color: terra coppa
Price:$1,249.00

  • Lightweight for Easy Learning
  • Quick and Simple Assembly
  • Worry-Free 30 Day Returns
  • Built for Kids and Built to Last
Size: 20″
Weight: 21.7 lb
Top features: child-specific geometry, air-sprung suspension fork, ergonomic saddle, disc brakes, tubeless-ready wheels, flip-flop stem
Age: 6 – 8 Years
Height: 46 - 51 in
Find the right bike

Rare AIR

The newly upgraded 20" woom OFF AIR 4 will take its Rider beyond the beginning stages of their mountain biking journey. Stable, responsive, and equipped with a high-performance front suspension system, durable components, and tubeless-compatible rims and tires, it provides best-in-class value in its category. Off-road capable and kid-tested, this mountain bike was ergonomically designed for growing bodies and developing abilities. The woom OFF AIR 4 is more than capable on cross-country trails yet, uncompromising on gravel, pavement, or wherever the spirit leads your Rider.

Specifications

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 

Gears

  • 9 speeds
  • SRAM X5 trigger shifter
  • SRAM X5 rear derailleur

Suspension 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

Wheels

  • 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

Headset

  • Fully integrated 1 – 1 ⅛" headset
  • Sealed industrial bearings

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

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

Saddle

  • Ergonomically designed to fit a child’s anatomy
  • Streamlined, mountain-bike-specific saddle design 
  • Side protection to lean against walls

Handlebars

  • 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

Seatpost

  • 27.2 x 250 mm
  • Anodized aluminum seatpost with insertion marks that indicate the minimum insertion depth
  • Quick-release seatpost clamp

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

Seatpost Clamp

  • Quick-release seatpost clamp for easy adjustments
  • Made from aluminum

Drivetrain

  • Lightweight, forged aluminum, 4.3" (110 mm), kid-specific cranks with narrow tread (Q-factor)
  • Narrow-wide chainring with 28 teeth in the front
  • Cassette with 11-32 teeth in the back
  • Flat pedals made from fiber-reinforced nylon
  • Chromoly axle and sealed industrial ball bearings

Brakes

  • Hydraulic disc brakes by Promax
  • Rotor diameter front/back: 140/140 mm
  • Ergonomic brake levers designed for a child’s hands

Weight

  • Bike weight: 21 lbs 11 oz
  • Max weight: 110 lbs combined weight of the Rider and cargo

Colors

  • Black
  • Terra Coppa

Enclosed Tools

  • 4 mm hex key for the stem and seatpost clamp
  • 8 mm hex key for the front wheel and pedals

Shipping Dimensions

45 x 26 x 9”

Sizing Chart

Model

Inseam

Height

woom OFF 422.8″ - 28.7″46″ - 51″
woom OFF 527.8″ - 33.7″50″ - 57″
woom OFF 630.3″ - 37.8″55″ - 65″
woom OFF AIR 422.8″ - 28.7″46″ - 51″
woom OFF AIR 528.3″ - 34.3″50″ - 57″
woom OFF AIR 630.7″ - 38.2″55″ - 65″

Unsure how to measure inseam? Can't decide between two sizes? Check out our What Size is Right?article

Geometry

Guarantee

The woom 10-year warranty

Inspiring children to love riding their bikes is our mission at woom. That's why we guarantee the premium quality of every bike down to the last detail with innovative technology and long-lasting materials.

We have full confidence in our bikes, which is why we offer a 10-year warranty on the aluminum frames, rigid forks, bars and stem once you've registered online.

Register now!

Returns

30-Day Return Policy (WOW 60-Day Return Policy)

If you buy a product directly from us that does not meet your expectations for any reason, you can return it within 30 days (WOW 60 days) of the purchase — no questions asked. We will refund the full cost of the product and pay to have it shipped back to woom. Please note: We are unable to refund the original shipping cost from when you first purchased the product. The refund for the cost of the product and return shipping cost will be processed within 5-7 business days upon receiving the shipment.

Return Procedures

If you are returning a product, please initiate a return by clicking the link below. Please read through the following tips if you are returning multiple items or upcycling to ensure your return process goes as smoothly as possible. Thank you!

Keys to Success

  1. If you are returning a combination of any of the following items that cannot fit in the same box, please do this in 2 separate returns. Items include: Any model bike, helmet, rack, freewheel, or fenders. For example, if you are returning a woom bike and helmet/large accessory, one return would contain the bike, and the other return would contain the helmet/ large accessory.
  2. The same rule applies if you are returning multiple bikes. Please do a separate return for each bike.
  3. Please ensure you are choosing the correct reason for return in order to get the correct return label.

Click here for return label

All domestic shipping costs after the initial shipment to you will be covered by us. We will send you a return shipping label and all you have to do is pack it up and bring it to the shipper.

For questions, please email usa@woombikes.com. You can also give us a call at 855-966-6872. We are here to help you.

The woom 10-year warranty

Inspiring children to love riding their bikes is our mission at woom. That's why we guarantee the premium quality of every bike down to the last detail with innovative technology and long-lasting materials.

We have full confidence in our bikes, which is why we offer a 10-year warranty on the aluminum frames, rigid forks, bars and stem once you've registered online.

Register now!

Product Variations

If you spot a difference between the product page and what you received, it’s likely due to a change in our supply chain. Our Customer Experience team is always here to answer any questions that you may have.

Simple assembly for simple rides

Your OFF-road adventure can begin shortly!

In just a few steps, your woom OFF will be ready for its first ride. Check out this video to find out exactly what to do.

Assembly instructions

Instructions for useService & Info

Frequently Bought Together:

READY Kids' Helmet
+2colors
READY Kids' Helmet

Our bike helmet comes in 3 sizes for kids aged 1 to 14. The innovative design guarantees the perfect fit, all-round protection, and ease of use. It's also ideal for roller skating and scooters.

46–50 cm (XS) | 50–53 cm (S) | 53–57 cm (M)

18.2 - 19.6" (XS) | 19.7 - 20.8" (S) | 20.9 - 22" (M)

$89.90
BEAM Bike Lights
BEAM Bike Lights

These powerful, rechargeable, weatherproof LED kids' bike lights are easy to attach and use. They run for up to 6 hours and turn off automatically when no motion is detected. For children aged 3 and up.

$44.90
TENS Bike Gloves
+4colors
TENS Bike Gloves

Our breathable cycling gloves designed to be easy for kids to put on, ensuring maximum grip on the handlebars and providing optimum protection for delicate little hands.
Sizes: 11,5 cm (5) | 13,5 cm (6) | 14 cm (7)

$19.90
GLUG Stainless Steel Bottle
GLUG Stainless Steel Bottle

Clean taste, glug after glug. Meet GLUG, our bicycle water bottle made of premium toxin-free stainless steel. Each GLUG also comes with our unique kid-friendly side-loading bottle cage which fits all standard diameter bike bottles.

$24.00

Ratings & Reviews

4.20Based on 10 reviews

Lightweight and good balanced bike for our 7 yr old kid. HOWEVER, very disappointed with the hydraulic disc brakes (spongy levers, rubbing rotors and squealing). Why do you put, at best, mediocre, brakes on a $1200 kids bike? Rather pay more upfront for better brakes and get to spend time with the kid on the trail, than consistently in the shop trying to fix. Read the reviews, I am not alone.

Reply fromwoom

Hello John, Thank you for providing us with your feedback, I'm really sorry to hear that you're having trouble with your brakes. That does not speak to our quality standards. I kindly ask that you contact our customer service team with your order number so that we can help rectify this situation. We hope to hear from you soon. Best, Your woom team

Reply fromwoom

Hi, HI John, Thank you for your honest feedback. We are really sorry to hear that you're having trouble with the brakes. On a $1,200 kid’s bike, you should be able to count on the quality and spend your time on the trail, not in the shop. Please reach out directly to our customer support team at [Email Address / Contact Form Link] and provide your order or invoice number. We will make sure to get this sorted out for you quickly and hassle-free. Best regards, your woom Team

1 person found this helpful
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Bike is great - slightly damaged on delivery

The ordering and delivery was speedy as promised - right on time. The bike itself is high quality for what it is and probably appropriatly priced. I was very frustrated when I unboxed and got the bike together which was very simple and discovered the rear derailer hanger was badly bent for some reason. I did not see any damage to the box so seems like possibly quality control of coming out of the factory there was an issue. I assembled this on a Saturday and Woom customer support was not available until monday. This was being gifted the next day. So I was luckliy able to find a local bike shop that was open late and able to repair the dmaged hanger. Once that happened the bike was great. My only suggestion. Improve the boxing to protect the Rear Derailer please from damage.

Reply fromwoom

Hello Corey, Thanks for providing us with your feedback. I'm happy to hear that you received the bike on time for your child's birthday, but I'm very sorry that it arrived damaged. That doesn't speak to our quality standards. Please contact our customer support team with your order number and any details or receipts regarding the local repair so our team can assist you further with this incident. Best, Your woom team

1 person found this helpful
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Satisfied

Great bike, fits like a glove and moves with the child. But it came with too few spacers so the headset was loose. Fortunately, my husband worked as a bike mechanic and immediately noticed the defect. Woom has compensated us in an accommodating manner. What's a pity is that it's too wide for s follow-me.

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4 people found this helpful
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Always impressed by the quality with Woom. We have the Go 3 Automagic as well. The bike is light weight, brakes feel great. Suspension is dialed in appropriately for their weight. The copper color also looks fantastic in person. It’s expensive but the quality is as great if not better than my $1200 cannondale hardtail mtb. For anyone who likes to bike a lot I think it’s well worth the price!

1 person found this helpful
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Top bike

So our child absolutely enjoys it! The price may be a bit excessive, but okay. Built-in components are really good. I think it's a shame that there are no original fenders for it!

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Woom Off Air 5 - absolutely brilliant

We bought the woom 5 for our son. It is well thought out down to the last detail — light, sturdy, safe. As a former cyclist, I immediately see what's right here: Geometry, brakes, sitting position — everything is neatly intertwined. You can tell that there were people at work who take children seriously. The service was also quick and friendly. A product that delivers what it promises.

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Woom Off Air 4

Our son loves the Woom Off Air and gets along great with it. Top workmanship and appearance. Dispatch and delivery went smoothly. Unfortunately, there is a star deduction for the very high price.

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My son rides this bike and is super happy with it - that's why we've been cycling a lot more often lately. Whether just to the outdoor pool or along the dirt roads and hills in the surrounding area. He enjoys both. Clear recommendation!

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The Best Bike Ever

Great air suspension great tires and every thing about this bike is just so so good but just maybe a little bit over priced but that doesn’t make the bike worse even though I don’t have it does not mean I can’t love it

4 people found this helpful
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