Trying to find quality kids 20″ wheel mountain bikes for 5 and 6 year old can be a bit of a problem as many manufacturers don’t start building them until the next wheel size up.  Thankfully, there are a number of manufacturers that have realised that it’s not just the big girls and boys that like riding through the muddy stuff!

At the moment there’s a shortage of all sizes and types of kids bikes, so we’ve also included a few other options that would be good fun to ride off road, but aren’t specifically mountain bikes. 

Best kids 20″ wheel mountain bikes

In this post, we take a look at our selection of some of the best kids 20″ wheel mountain bikes that are currently on sale in the UK for kids around 5 years of age. If your child is going to be riding on all types of surfaces, such as grass, tarmac and road, then a mtb might not be suitable for them, so please take a look at our article on the best 20″ wheel hybrid bikes, which will probably be more suitable.

Sponsored Content Start

Want to make some quick cash from that too small bike?

Do you have a good quality kids bike that's been outgrown and you've been meaning to sell on? 

Luckily The Bike Club are making it REALLY EASY for you to sell on old kids bikes. 

Just get an online valuation for your old bike, and if you're happy with the price they'll send a courier round with a bike box to pick it up. 

No hassle - just more space and more cash for the next size bike. Easy! 

Sponsored Content End

Black Mountain HÜTTO (From £449)

Cycle Sprog reviewed and recommended bike

BLACK MOUNTAIN HUTTO Key Stats:

Price: £449
Typical Age range: 6 – 8.5 years
Height range: 118cm to 134cm
Bike weight: 8.3kg
Brakes: Tektro V-brake with adjustable brake levers;
Gears:  7 speed – grip twist shifter [Sunrace 7 speed, 11-32 x 32T]
Frame: Lightweight adjustable frame – two sizes
Tyres: Kenda Small Block 8
Other features:  quick release Go-Lo seatpost; balance bike conversion kit (extra cost)
Available colours: Neon Green, Azure Blue, Orange, Purple
Black Mountain Bike Warranty: 3-years on frame and forks; 2-years on non-consumable components. Warranty can be passed onto new user if you sell on (must inform Black Mountain of change of ownership)

Black Mountain is really taking the kids bike market by storm with their “growing bikes”.   They’ve now introduced a couple of larger wheel sizes to the range, with the HÜTTO being the 20″ model. The premium specification HÜTTO Trail (pictured above) comes kitted out with disc brakes and front suspension, which is perfect if you’re planning on tackling a lot of off road riding.  All models come equipped with 7 speed SRAM Twist shift for hills.

Aimed at kids aged roughly between six and eight and a half, Black Mountain uses its EPOK growing frame design so it can start off in small pedal bike mode and be extended to large pedal bike mode as your Sprog grows.

At the current time, this has the added advantage of providing peace of mind that you’re going to have a bike that lasts for a while as your child grows. With the unprecedented situation, we currently find ourselves in we don’t know what’s going to happen with stock levels of kids bike over the next few months. If your child is at the lower range of the sizing for the Hutto (118cm to 134cm) this might be a wise choice as you’ll have a bike that will grow with them.

The HÜTTO  comes in three versions and clicking on the links below will give further details for each version:

• The standard specification HÜTTO (£449), comes supplied with v-brakes and all-purpose Kenda tyres;
• you can then opt for the HÜTTO Disc (£549), which is equipped with Tektro mechanical disc brakes, upgraded sealed cartridge bearing wheels and grippier Schwalbe Black Jack off-road tyres, and finally
• there’s the HÜTTO TRAIL (£649) that adds a pair of 50mm travel Spinner Grind Air suspension forks to the DISC version.

The HÜTTO is available in four vibrant colour options – orange, green, purple and blue and comes with a three-year warranty.  We’ve reviewed the slightly smaller 18″ wheel Black Mountain KAPEL and were very impressed with it’s slack geometry and mountain bike inspired styling. 

BUY NOW:  Black Mountain Bikes are only available direct from their website.  

Cube Acid 200 2021 (£399)

Cycle Sprog reviewed and recommended brand

Key data for the Cube Acid 200:

Price: £399
Bike size: 20″ wheel
Brakes: Alloy V-Brake with Power modulator
Frame: Aluminium Lite 6061
Forks: Rigid Hi-Tensile steel fork
Gears: 7 speed – 13-34T cassette, 36 tooth single chainring and Shimano SL-RS45 Revo Shifter
Tyres: Cube IMPAC Streetpac 2.1
Available colours: Green/white
Weight: 9.4 kg
Warranty: Frame 6 years; rest of bike 2 years

Cube have a good range of different style kids bikes, and the Cube Acid 200 is a good choice if you’re looking for the type of versatile bike that is equally suited for riding on trails and roads. It’s not an all out mountain bike (Cube have other, more expensive models for that!) but we’ve included it here as we know many people want a bike that serves more than one purpose and it seems reasonably easy to get hold of at the moment. 

Cube’s bikes are renowned for being robust – the German engineering means they’re build with longevity in mind – we have reviewed a number of their bikes over the years and have always been very impressed. 

Buy now: Cube Acid 200  

Vitus 20 Plus (RRP £360)

Cycle Sprog reviewed and recommended bike

Vitus 20 Plus key data:

Price: £360
Minimum height: 120cm;
Inside leg:52cm;
Bike weight: 9.8kg;
Brakes: Tektro M300;
Frame: Lightweight Alloy Frame;
Tyres: Vee;
Available colours: Silver;
Warranty: 5 year frame and forks, 2 year components

The Vitus 20 Plus is an eyecatching option for kids looking to get out on the trails. Released late October 2018, it’s a 20″ wheel bike with plus size (2.6″) tan wall tyres – which will really make your Cycle Sprog stand out.  It’s not all about looks though – it’s built around a lightweight 6061-alloy frame, with stopping power provided by Tektro mechanical disc brakes which have adjustable brake levers for small hands.

We’ve reviewed this bike and our test rider really enjoyed riding the Vitus on a mix of on and off road surfaces in various weather conditions. You can read our full review of the Vitus 20+ here. 

BUY NOW: Vitus 20 Plus

Nukeproof Cub Scout 20 2021 (£649)

Nukeproof Cub Scout key data:

Price: £649
Standover height: 518.6mm
Bike weight: 10.12kg
Brakes: Tektro M276 Kids Specific Hydraulic Brakes (Direct Post mount) with 160mm rotors
Frame: Custom butted hydro-formed 6061 alloy frame and fork
Gears:  8 speed – 32T crankset and 11-34T cassette with Shimano M310 rear derailleur
Tyres: Vee Rubber Crown Gem 20″ x 2.6” Skinwall, MPC Compound
Additional features:  Uses bolt-thru axles rather than quick-release
Available colours: Bullet grey and yellow
Warranty: 5 years frame 2 years components

Nukeproof have designed a proper little mountain bike with the Cub Scout.  They’re better known for their World Cup winning bikes, but have turned their attention to making a bike that they hope will inspire the next generation of champions.  

The Nukeproof Cub Scout is obviously a lot more expensive than a standard kids bike, but you do need the right tools for the job.   If mountain biking is your thing and you plan to spend every weekend and holiday out on the trails then your child (and you) are really going to appreciate having a “proper” bike to get them up and down those hills. 

The geometry of the bike is “slacker” than a standard 20″ wheel kids bike, which means a riding position much more suited to mountain biking than the upright position needed for riding around the park.  The components are all sized for small riders, and have been sourced from their existing partners, so you know you’re getting a good quality machine. Enjoy the ride! 

BUY NOW: Nukeproof Cub Scout 20 2021

Merida Matts J20 Plus (£430)

Key data for the Merida Matts J20 Plus:

Price: £430
Bike size: 20 inch wheel
Standover height: 483 mm
Frame: 6061 double butted aluminium
Forks: Merida aluminium fork
Gears: 7 speed – 28 tooth single chainset with 14-34T cassette and Shimano Altus thumbshifter
Brakes: Tektro HD-M275 hydraulic disc brake 160mm front and 140mm rear rotors
Tyres: CST Jet C1820; 20″ x 2.4″; wire bead
Available colours: Light Blue, Orange
Weight: 9.47 kg (Merida website)
Warranty: Frame lifetime, rigid aluminium fork 5 years

The Merida Matts J20 Plus is the smaller sibling of the 24″ wheeled J24 Plus, with a similar specification apart from having a 7-speed drivetrain. It features plus tyres to give additional comfort and improved grip which is always useful whether going up, down or in corners and a set of hydraulic disc brakes to bring things to a halt.

Buy New: Merida Matts J20 Plus 

BMC Blast 20 (£600)

Key data for the BMC Blast 20:

Price: £600
Bike size: 20″ wheel
Age: 5-8 years
Rider height: 110-135 cm
Frame: Lightweight double-butted smooth weld aluminium with powder coat finish
Forks: Lightweight aluminium with powder coat finish
Gears: 8 speed – 32 tooth single ring chainset with 11-34 tooth cassette and SRAM X4 thumb shifter
Brakes: Tektro HD-M286, short reach levers, 140mm rotors
Tyres: Kenda Booster 20×2.4″
Available colours: Bronze
Weight: 9.2 kg
Warranty: 

The BMC brand started in Switzerland in 1994 and pride themselves as being ‘designed by geeks, built by machines, pushed to the limits by the world’s fastest athletes’.

The Blast is their junior mountain bike offering for kids aged from 5 up to about 8 years old, and comes specified for fun times. Built around a lightweight double-butted frame and aluminium forks there are 2.4″ ‘plus-sized’ tyres to give high levels of grip and comfort. BMC have specified powder coating of the frame and forks rather than traditional solvent-based wet paint, as a more durable and ecological finish. The gearing is 8-speed with a single chainring, and changes are made by a SRAM X4 thumb shifter. BMC have specified Tektro hydraulic brakes with 140mm rotors for braking duties.

Buy now: BMC Blast 20

Orbea Laufey H30 (£479)

Key data for the Orbea Laufey H30:

Price: £479
Bike size: 20″ wheel
Brakes: Shimano MT400 Hydraulic Disc
Frame: 6061 lightweight aluminium
Forks: 6061 lightweight aluminium (no suspension)
Gears: Shimano Altus 9-Speed with 11-36T cassette, 32T single chainset and Shimano SL-M2010 thumb shifter
Tyres: Kenda Booster K1277 20×2.20″ 30TPI
Available colours: blue grey/red as shown here or black/rainbow
Weight: n/a
Warranty: 2 years - register bike within 30 days for lifetime warranty on frame and forks and 3 years on paint, varnish and corrosion

Orbea appear to have taken their adult Laufey range and shrunk it so that kids can have a blast on the trails too!

Buy now: Orbea Laufey H30 20 inch 2021

Kona Makena 20 Plus (£419)

Key data for the Kona Makena:

Price: £419
Bike size: 20″ wheel
Standover: 538 mm
Frame: Kona 6061 Aluminum Butted
Forks: Rigid – Kona Project Two JR CrMo
Gears: 7 speed – 14-34T cassette, 28 tooth single chainring and Shimano RevoShift shifter
Brakes: Tektro V-Brake
Tyres: Vee Tire Crown Gem 20×2.6″
Available colours: Matte Blood Orange with Metallic Black and Blue decals
Weight: n/a
Warranty: 2 yr on complete bicycle. Extended warranty (for original owner) if bike registered within 3 months of purchase.

Buy now: Kona Makena 20″

Giant ARX 20 (£349)

Cycle Sprog reviewed and recommended bike

Key data for the Giant ARX 20:

Price: £349
Bike size: 20″ wheel
Brakes: v-brake – alloy, linear-pull
Frame: ALUXX-Grade Aluminum frame and forks
Gears:  8 speed – Shimano Altus derailleur and shifter with a single 32T chainset and 12-32T cassette
Tyres: Innova IB-3010, 20×1.5
Available colours: Lemon Yellow
Weight: 8.76 kg
Warranty: Frame - lifetime, Forks - 10 years, All other components - 1 year

The Giant ARX 20 is a good quality lightweight bike, that is equally at home on the trails and the tarmac.  We’ve included it here as it’s a good all round versatile bike that may come in stock before some of the more specialist mountain bikes.

We were lucky enough to have testers Katherine and Jessica put one through its paces. You can read their thoughts in the review here, or read our first impressions review here.

Buy new: Giant ARX 20

Buy secondhand: Giant ARX 20 from eBay

Sponsored Content Start

Want to make some quick cash from that too small bike?

Do you have a good quality kids bike that's been outgrown and you've been meaning to sell on? 

Luckily The Bike Club are making it REALLY EASY for you to sell on old kids bikes. 

Just get an online valuation for your old bike, and if you're happy with the price they'll send a courier round with a bike box to pick it up. 

No hassle - just more space and more cash for the next size bike. Easy! 

Sponsored Content End

Orbea MX20 Team (from £359)

MX20 Team key data (V-Brake):

Price: £359
Minimum height: 115 cm
Brakes: Alu V-Brake
Frame: Orbea MX 20 Alu
Tyres: Kenda Booster K1277 20×2.20″ 30TPI
Available colours: Blue/Red, Purple/Pink, Red/Black
Warranty: 2 years - register bike within 30 days for lifetime warranty on frame and forks and 3 years on paint, varnish and corrosion

MX20 Team key data (Disc):

As above, except;

Price: £419
Brakes: Shimano MT400 Hydraulic Disc
Frame: Orbea MX 20 Alu only disc
Available colours: Blue/Red, Purple/Pink, Red/Black, Mint/Black
Warranty: 2 years - register bike within 30 days for lifetime warranty on frame and forks and 3 years on paint, varnish and corrosion

The MX24 series features in our 24″ wheel selection of kids mountain bikes, so it seems only fitting that its pint-sized sibling should be featured too. This Team version comes with a better specification than the Dirt shown above.

The MX20 Team comes in two versions, with a choice of v-brake (£359) or disc brakes (£419).   As you can see from the picture (the Orbea MX 20 Team Disc version is shown) the bike just oozes purposefulness, with its paintwork and 2.1 inch tyres back and front it looks desperate to be let off the leash.

The specification for the MX20 Team Disc is good, with a smattering of own-brand components in the usual areas (bars, stem, seatpost) matched to named components such as the Shimano MT400 hydraulic discs, that have a strong reputation for good performance at a palatable price. The drivetrain comprises a 9 speed setup with Shimano Altus Shadow rear mech and shifters and matches a 34T single chainring up to an 11-36T cassette to give a good spread of ratios.

Shimano updated their groupsets earlier in the year, and in doing so the technology from the higher in the pecking order XTR an XT trickles down to the groupsets below, making them really great value. This is a good move by Shimano and gives the MX20 bang up to date kit, which is great to see on a 20″ wheeled bike.

BUY NOW: Orbea MX20 Team

BUY SECONDHAND: ORBEA MX20 TEAM from eBay

ORBEA MX20 DIRT (rrp £309)

Orbea MX20 Dirt key data:

Price: £309
Minimum height: 115cm
Bike weight: kg;
Brakes: Alu V-Brake
Frame: 6061 Aluminium frame with hi-ten steel fork
Tyres: Kenda Booster K1277 20×2.20″ 30TPI
Available colours: Blue/red, black/red, purple/pink;
Warranty: 2 years - register bike within 30 days for lifetime warranty on frame and forks and 3 years on paint, varnish and corrosion

I have a soft spot for Orbea – the bike builders from the Basque country – as I have owned, ridden and loved one of their road bikes. I also like the fact that they take kids bikes seriously, and are creating some fine examples that are scaled to suit.

The MX20 Dirt features dialled in components to make things fit just right for small hands and bodies. There are 7-speeds to choose from and a Shimano thumb shifter to help you change between the useful range of gears that comprises a single chainring at the front to keep things nice and simple. Stopping is taken care of by v-brakes, and there’s a set of chunky tyres to give grip during your (socially distanced) off-road adventures. It’s available to buy in three colour schemes.

BUY NOW: Orbea MX20 Dirt

BUY SECONDHAND: Orbea MX20 Dirt from eBay

Cannondale Cujo 20 Plus (rrp £349.99)

Cannondale Cujo key data:

Price: £350
Typical age range:5 to 9 years;
Bike weight: kg;
Brakes: Tektro mechanical disc w/ 160mm rotors;
Frame: SmartForm C2 Alloy frame;
Tyres: Kenda Slant 6, 20 x 2.6″;
Available colours: Orange;
Warranty: Frame - Lifetime, Components - 1 year

Exploring the ‘plus bike’ theme, Cannondale has the Cujo model in its lineup that comes with chunky 2.6 wide tyres to give your rider suspension over the roughest terrain.

Fitted with Tektro cable operated disc brakes, the Cujo has been designed for tackling hills with a 7-speed drivetrain that has a 30 tooth single chainring at the front and a wide-ranging 11-34 tooth cassette to lend a hand. Gear changes are handled by a Shimano Tourney Revo Twist Shifter.

BUY NOW: Cannondale Cujo 20 Plus

Whyte 203 (RRP £499)

Whyte 203 key data:

Price: £499
Brakes: Tektro M-275 hydraulic;
Frame: 6061 Alloy;
Tyres: Schwalbe Smart Sam 20″ x 2.35″;
Available colours: Olive/orange, midnight/lime;
Warranty: Frame: 2 years - can be extended to 4 years if registered within 28 days of purchase. Doesn't cover racing, jumping or tricks

Whyte mountain bikes are some of the most desirable bikes around at the moment – go to any trail centre and you’re bound to see loads of them in the youth 26″ wheel and larger adult sizes.  The 203 is their 20″ wheel offering for the younger age range and is built around a lightweight aluminium frame in keeping with the current trend for long and low geometry.

Cabling is routed internally so there’s definitely a clean look to the frame, plus there’s a set of 140mm hydraulic discs to keep things in check. The transmission comprises SRAM’s X4 grip shift to change between the 8 gears, with a 28 tooth chainset matched up to an 11-36T cassette to give a good range to tackle a variety of terrain.

We first saw the Whyte 203 at the 2018 Cycle Show at the end of September, which is going back some time now, but it was certainly a great first introduction to this cracking looking little bike.

BUY NOW: Whyte 203 

BUY SECONDHAND: WHYTE 203 from eBay

The best kids 20″ wheel mountain bikes

So there you have it. A great selection of kids 20 inch wheel mountain bikes that will have them tearing up the trails in no time. This is just a small selection of what is currently available, so if you feel another bike should be added to the list, please get in touch via Facebook as we’d love to hear from you. Happy riding!

Please check out some of our other articles:

• The best 20″ wheel hybrid bikes for kids aged 6 to 8
• The best road racing bikes for kids with 20″ wheels
• The best kids 24″ wheel mountain bikes
• The best road bikes for kids with 20 inch wheels
• Buying a kids mountain bike – things you need to know
• The best kids 26″ wheel mountain bikes
• The Polaris Fang kids cycling jersey
• Deals on Kids Mountain Bikes – discounts available already
• The best full suspension kids mountain bikes

This post about the best kids 20″ wheel mountain bikes contains affiliate links. The small commission we get if you buy through these links helps us keep running the Cycle Sprog website. Thanks for your support!