Diamondback Cobra 20 Complete Kids Mountain Bike Review

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Diamondback Cobra 20 Complete Kids Mountain Bike Review

Diamondback Cobra 20 Complete Kids Bike is ideally the next step in your child’s riding journey. It is one of the best selling mountain bikes, which is made for some serious fun on the trail.

Diamondback is a famous bicycle brand that designs and manufactures fantastic bikes for the entire family. The Cobra 20 mountain bike is easy to maintain and does not require much handling skills.

It is a perfect, high-end bike for your whole family, which has fantastic features like Hi-Ten MTB steel frame, six-speed Drivetrain, Shimano gear and shifter, 20-inch alloy wheels, and much more. It is beautifully designed and gives you full control while having fun.

Read the Diamondback Cobra 20 Complete Kids Bike review 2021 here and check its fabulous features and advantages, which makes it a bike of a lifelong interest.

Best Suited to Whom?

The Cobra 20 Complete Kids Bike by Diamondback is an ideal buy for both boys and girls, who want some fun riding and getting full control of the bike. It is designed for a kid and not an adult.

Its braking system is superb and brings the bike to a halt in the middle of the trail, without giving a shock. It does not need much maintenance and is here to stay for long.

Kids in the height range of 45 to 56-inches and the age range of 6 to 10 years can make the best use of this beautiful mountain bike by Diamondback.

Diamondback Cobra 20 Complete Kids Mountain Bike Assembly, Design and Build Quality


The assembly of the Cobra 20 Kids Bike is not so difficult. This bike comes 85% assembled, and all the parts are sealed in a box. You need to install and adjust the components as per the instruction manual that comes along with the package.

If you are not an expert with handling machines, then you can bring it to any bike shop and get it assembled.

Design and Build Quality

The design of this Diamondback’s Mountain Bike is excellent for kids who are progressing to a new bike to experience more adventure. Its drivetrain provides six speeds so that you can ride on flat trails as well as hills.

The comfortable SunRace shifters enable secure handling of the handles while changing gears. The linear-pull brakes provide reliable braking system with convenient hand-brake levers. The tires are wide and bumpy, which offers enough suction on any surface.

Its design ensures a smooth ride with the help of a front suspension fork. The seat is padded for added comfort, and the bicycle is brightly colored to make it more attractive. The wheel size is 20-inch, ideal for a kid’s bike.

But. If you want more capacity, then you can check the Diamondback Cobra 24″ Youth bike review. The build quality of this bike is not less than a professional mountain bike. It has a very sturdy Y-shaped steel frame, made of Hi-Ten MTB steel.

This feature makes it an extra durable machine, which means even if the kid hits the bike anywhere, the bike will remain intact. It weighs 34 lbs. The Shimano Revo Grip shifters enable swift changing of gear from one level to another. It is a comparatively cheap bike with the right quality components.

Diamondback Cobra 20 Complete Kids Mountain Bike Features


The Diamondback Cobra 20 Kids Mountain Bike has high-grade 20-inch alloy wheels. The alloy is lighter than steel, which means these wheels provide more acceleration to the bike.

Your kid will find it easy to ride through rough terrain. The rims are also reliable, which resist the opposing force of the jerks and bumps. This wheel size is ideal for a smooth and fast ride.


The frame of this mountain bike is made of Hi-Ten MTB steel, which makes this bike very robust. Its standover height is 19.5-inches, and the top tube is 16-inch long, making shorter riders to reach the handlebars comfortably.

This bike can take any bumps or jerks with ease without getting affected. Its frame is durable, which makes it a long-lasting bike. This frame is lighter, yet strong enough to take a kid’s rough play.


Shimano’s Gear and Shifters gives a magical performance by this bike. It is reliable and has great fluid mechanics, which enables swift gear shifting at the right time. A total of six gears help your kid to keep up on hills.


Safety is an essential factor when it comes to buying a mountain bike. No matter how smooth the gear system is, a proper braking system is necessary for the safety of the rider.

The mechanical rim brakes ensure that your kid is safe and will not fall on applying sudden brakes. The linear pull-brakes proffer a reliable power which brings the bike to an immediate halt.
Shimano’s center-pull cantilever brakes bring immense braking power.


Suspension of this Diamondback mountain bikes for kids is ultimate. Any journey can become smooth and comfortable if the bike has a sound suspension system. The HI Zoom 40mm travel fork makes the riding experience joyful.

Although the fork wears out in a few months, hence needs to be replaced. Even though this bike is designed for kids, but the fork is made for tough roads.


Shimano Revo Twist shifters enable easy changing of the gears. It has one crank wheel with a double chain guard. It gives full control to the rider and makes the process simple.


The tires of this mountain bike are 2-inch knobby tires, which can overcome any obstacle on the way. They offer enough suction to enable a smooth ride.

Weight Capacity

This mountain bike can take weights of kids in the age range of 6 to 10 years. Anyone more than this age may not be able to ride it comfortably.

Diamondback Cobra 20 Complete Kids Mountain Bike Warranty

This bike has very well built quality which tends to provide you the safest and comfortable ride. Also, the brand offers a lifetime warranty on its frame and 5 years warranty on the suspension of the bike.

This bike also provides a warranty of 1 year on various suspension parts. With this, the brand also provides many benefits like providing prompt, courteous, and the best customer service.

Diamondback Cobra 20 Complete Kids Mountain Bike Pros & Cons


  • It offers smooth shifting of gears with Shimano drivetrain
  • The frame is super sturdy due to Hi-Ten MTB steel
  • The 20-inch alloy wheels make the ride smooth
  • Front suspension fork sucks up the bumpy shocks of the uneven terrain
  • The linear-pull braking system is potent
  • Shimano shifters enable smooth shifting of gears


  • No water bottle holder
  • No kickstand


From the above Diamondback Cobra 20 Complete Kids Bike review, it is clear that it is one of the most-suitable mountain bikes for kids. It is solidly built and has impressive features like 20-inch alloy wheels, 2-inch knobby tires, a linear-pull, reliable braking power, Shimano drivetrain, front suspension fork, and much more.

Even though its a kids bike but its built and features are no less than an adult mountain bike. It offers a great riding style for kids in the growing age. It is also a cheap bike and is rated as one of the best-selling mountain bikes under $200.This bike will last longer and keep your kids motivated and confident ride after ride.

FAQs of Diamondback Cobra 20 Complete Kids Mountain Bike

What if my kid is heavyweight? Will this bike takes its weight?
Yes, this bike can take heavyweights of a kid in the age range of 6 to 10 years, because it's rim and wheels are made of alloy.
Does this bike have coaster brakes?
No, Cobra 20 mountain bike comes with only hand lever brakes.
How can I replace the tire?
You may need to search for the 20” x 1.95” Schrader valve tube if the tire becomes flat. There is no need to change the tire.