Bike 20" • 16.76 lbs

Child 6 - 9 years • 45"-51"

$ 449.00

ships same or next business day

Free UPS ground shipping

Money back guarantee

The intro to gears!

The woom 4 is a dynamic bicycle that introduces children to gears! Our SRAM X4 8-gear shifter expands the possibilities for the rider. Whether they are out adventuring in an area with hills or going on a long commute in town, this 20" bike is as powerful as the growing child demands it to be.

Hassle-Free Assembly: Our Austin, TX based team of qualified mechanics prepare and quality check each bike prior to shipment. All tools and easy-to-follow in-home assembly instructions are included

The 20” woom 4 takes bike riding to the next level. Bike weight: 16.46 lb; Designed for ages 6 to 9 years or overall height 45"-51”.

Bike: This all-terrain bike introduces kids to gears. With 8 gears and light Kenda off-road tires, it is perfect for exploring and longer rides

Shifting gears: The SRAM X4 8-speed shifters boost the joy of riding and expand the rider's range. The gear ratio is designed to handle any terrain, from steep climbs to long descents

Size: 20"
Weight: 16.76 lbs

Age: 6 - 9 years
Height: 45" - 51"

Available variants:
Red / Blue / Green / Purple

KENDA Tires: all-terrain

Tires influence riding behavior. Because of this, we have chosen tires that work on a wide range of applications. Roads, streets, or even into a path in the woods... our tires are all-terrain!

KENDA tires safely ride on a variety of surfaces and help absorb bumps.

At 1.5' tire width, we offer a tire that is high-performance.

Kenda shaves off weight (keeping our offering light in weight) and rolls well.

Because of an excellent rubber compound, KENDA tires can work in wet or dry grounds.

We develop smart standards

The length and spacing of our crank are adapted for a growing child's body. With an optimal Q-factor, our crank provides multiple benefits.

The length of the crank fits the length of the legs.

Ergonomic length ensures a perfect fit (B)

Low, child-friendly Q-factor ('Q-Faktor'): horizontal leg spacing suitable for the pelvic width: 141 mm (5.6 inches).

Crafted with super-light aluminum

Integrated chain ring

Chain-protection ring prevents pinching and protects the pants

We develop smart standards

The stem is smooth, light and inviting to the child. Additionally, the stem does not have any protruding screws, which protects the young rider's knees.

With just one screw, the stem can be simply plugged in and tightened

All other adjustments are already done by professional woom bike technicians

Unique smooth surface that minimize the risk of injury, and forged, 40mm aluminium

The woom stem is exceptionally smooth and light

We develop smart standards

The seat height can be adjusted quickly and easily with the quick-release seat clamp. The lever is long enough that children can operate it by themselves - without any tools!

Long lever with secure clamping force

Handy screw for fine adjustements

Locking screw prevents twisting of the clamp

Raising the Bar

The aluminum frame is the heart of the bike: elaborately developed geometry. We make new beginnings easy.

Weight-optimized, certified AA-6061 aluminum frame construction

Long wheelbase for stable riding

Ergonomically designed for safe balance

Low body for easy on and easy off

Specially developed fork guarantees stability

Multi-layer varnish with over-painted embroidery

We develop smart standards

The seat is one of the most important contact points between the child and the bike. It significantly improves the ride quality and experience.

Comfortable padding to ensure the growing child rides confidently

Anatomically adapted and designed to perfectly fit the hip bones of the child

The premium and non-toxic seat cover does not contain any chemicals

Designed with a protective side fabric to protect the saddle, i.e. lean against a wall or place on the ground when not in use

We develop smart standards

Designed so that steep uphill climbs are a piece of cake, our SRAM 8-Speed grip shift puts the young rider in full control of their next adventure.

SRAM SX4 – 8-Speed Grip Shift

High-quality Jagwire Bowden cables react to minimum manual power during shifting

All gear installation and fine-turning is already done by woom

Gives your child full control with smooth transitions while riding

We develop smart standards

woom bikes are equipped with two independent and powerful V-Brake brakes. The levers fit ergonomically for hands of the young but growing child.

Ergonomic, aluminum die-cast brake levers

Levers can be operated with a small amount of force from the hand

The range can be adjusted perfectly using adjustable screws

High-quality Jagwire Bowden cables react to minimum hand force

The V-Brake brakes can be used with little effort: children love the control offered by woom brake

We develop smart standards

The seat height can be adjusted quickly and easily with the quick-release seat clamp. The lever is long enough that children can operate it by themselves - without any tools!

Long lever with secure clamping force

Handy screw for fine adjustements

Locking screw prevents twisting of the clamp

Highlights at a glance

These are the most important features for children at this age:

All components that are specifically designed with safety in mind have the kidsafe PLUS seal. Click the icons to find out more.

Riding a bike is more than just fun in exercising. Discovering the world means expanding one's horizon.

Christian Bezdeka

Founder of woom

Bike geometry

A Wheel / Tire size 20"
B Cockpit / Grip height 29.33
C Steering angle 68°
D Horizontal toptube length 16.93"
E Wheelbase 32.48"

F Seattube angle 71.5°
G Minimum Seat Height 21.65"
H Maximum Seat Height 27.56"
I Crank length 4.33"

Specifications

Frame

Frame Material: Light and high quality A-6061 Aluminum
20" wheel size providing agile yet good natured riding characteristics: low step in height, very low minimum seating position, long wheelbase, very forgiving geometry Set up provides maximum stability, and excellent balance resulting in increased satisfaction
Continuous seat post design allows for maximum saddle height adjustment

Fork

light unicrown fork made out of aluminum
1" shaft - designed for ease of steering

Headset

semi-integrated 1" headset = sealed ahead set made out of steel and aluminum
integrated ahead clamp

Stem

Forged Aluminum - 40mm, +/- 10°
no protruding screws in this fully integrated and proprietary clamp design, we call it the knee-friendly design
the handlebar is connected with two 6mm bolts

Handlebar

wide, ergonomic, and light aluminum handlebar for more control
sand blasted and black anodised

Handles

reduced diameter for extra small hands
free of softeners and pollutants
grippy diamond structure
handle bar ends contain rubber plugs for additional cushioning and safety

Crank

Light forged aluminum cranks with 110mm length and low Q-Factor
(low width between both legs)
Beginner ratio: 28T front and 11-32 rear
plastic pedals
molded cartridge chamber
Easy to operate V Hand brakes

Brake

Two independent hand brakes (No Coaster Brake)
Mini V-Brake with levers suitable for small hands
brake lever with reach adjustability and ergonomic fit for very small hands
high quality Jagwire bowden cable for low friction and ease of operation

Shifter

1x8 gears
SRAM X4 twister shifter for ease of shifting
SRAM derailleur with short cage

Wheels

Super light Soopa-Doopa-Hoops Aluminum rims
small Aluminum hubs for extended leg room at the rear wheel
sealed bearing hubs
wheel can be installed and removed with 5mm allen wrench
20 Niro spokes 1.8 straight spokes

Tires

Kenda Small Block 1.5" x 20 light weight low profile balloon tires offer great damping, rolling performance and a lot of grip
Schrader valves (car valves) to inflate easily

Saddle

Age specific and ergonomically designed and molded
Free of pollutant and toxins
side safeguard to lean against wall

Seat Post

Anodized aluminum seat post
integrated maximum insertion indicator

Seat Post Clamp

Aluminum quick release seat clamp with long lever for ease of use and operation
clamp is safely secured against unnecessary movements

Enclosed Tools

1 long allen wrench for headset, 15 wrench for pedals

Weight

16.76 lbs

Colors

Red, Blue, Green, and Purple

Shipping Dimensions

39.5" x 8" x 22"

Bike Information

Max wieght: 154 lbs (70 kg). At woombikes USA, we reserve the right to make changes to the information on our website at any time. Weights are based on time of information publication and are up-to-date. Weights may vary slightly, as we are always improving our bikes.

This is how we deliver your bike:
5 min., ready, go!

Questions about assembly?

assembly instructions for woom 4 pdf, 6 MB

upCYCLING –
woom bikes grow with you
(optional purchase)

Kids grow quickly. Size and fit is important. Avoid making compromises and choose the right size bike for your child. This unique program is available to all of our customers and will allow you to size up to the next bigger bike as your child grows.

40% back of the original purchase price.
We will reimburse 40% of the original bike purchase price when you order a new woom bike within 24 months.
Your old woom bike must be less than 2 years old and in rideable condition. Rideable condition means that you allow your child to ride the bike.
We manage the return shipping of your old bike. We will provide you with a prepaid return label.