BMX Bicycle

What Age Is A 20 Inch BMX Bike for?

What Age Is A 20 Inch BMX Bike for

This question might be hard to answer. There is no standard bike size for every kid at different ages, as each of them has a different growth rate depending on their living condition. One seven-year-old kid’s height and weight vary from others.

Your kids want you to buy him a BMX bike. At the same time, you want that child to stop sticking his head to the TV or any electronic devices and have some outdoor fun. Two ambitions share one common goal. And now comes the real question, what then?

First thing first, let’s answer these following questions in mind:

How A 20-inch Bike Differs From Others?

The Mongoose Legion L20 BMX Bikes
The Mongoose Legion L20 BMX Bikes

The number 20 here is assigned to the size of the bike’s wheels. Conventionally, this is a standard size for most BMX bikes, which is followed by 14″ and 16″, and then 24″,26″ and wider. This wheel size is also the primary choice of the BMX community.

Why Do We Buy A 20” Bike for The Kids?

Let’s go through each growing stage of children:

Toddlers (2-4): Kids in these ages cannot reach the pedal. What they need at this age is a balance bike, which resembles the original “hobby horse,” back in 1818. However, for those who can actually pedal, a 12-inch bike would be appropriate.

Small kids from 5 to 9: In this stage, the perfect pedal bike for them would be 16 inches. You might want to search BMX Caiden on YouTube in this case, an 8 (or 9) year-old talented kid riding a 16-inch custom BMX bike and going for a massive jump with it.

Larger children from 7 – 10: this is the right stage for your kid to make a move on a 20-inch BMX bike. Plus, in this case, height does matter; your child could grow to an appropriate size for a 20-inch bike at the age of five. If not, don’t worry; they will be that tall when reaching eight or nine. Down here, we will give you the most accurate size calculator that we can do, but if you have any inquiries or want more detail, don’t hesitate to leave a comment below. It is our estimation that if a child is higher than 118 cm ( around 46 inches), then he (or she) is ready to have the first ride on the 20”, but for more precaution, we highly recommend height around 120 to 135 cm would be appropriate. One side note for you, a 20” will mostly have gadgets coming alongside. Therefore, try to give them a thorough guide about their function and allow them to go with them. Sometimes, you can use the inner leg measurements to ensure that the bike size suits your kids.

How Can I Know If It Fits or Not?

The Dynacraft Magna Throttle Boys BMX Bikes
The Dynacraft Magna Throttle Boys BMX Bikes

Having your bike check cannot be taken lightly, as you want your little one to be comfortable, brave, and can land both feet on the ground (they can tiptoes, which means they are so courageous to do so) and the handlebars with ease (no body and arm overreaching). On top of that, you want that bike to have the right gap between the seat and handlebars so that your children could comfortably relax their arms. Also, the gap needs to be enough for the kid to reach for brake levers and gear shifters. This aspect could be adjustable if required.

So far, we have been discussing how age is having an impact on the size of the bikes. Yet, one critical thing you need to remember; age does not affect how to get a suitable bike for your child; or at least, it alone is not enough. Simply, just let your little champ hop on and try out a few bikes and see which one fits them the most.

Ride and Test

To make sure that your kid gets the right bike, down here is a list of a critical element, you should carefully observe when testing a bike.

  • Take a seatWhen your kid is sitting on the bike, go and see if he (or she) is comfortable if their foot can land on the ground or not. Otherwise, this could damage your child’s initial experience about riding and might lead to unwanted injuries in an unsupervised ride.
  • Level the Pedalsfor this criterion, there are two things that you need to take note of. First of all, if your child’s knee bumps to the handlebars while riding, that means the bike is too small. By contrast, if you see that your child keeps stretching his legs when pedaling, the bike is merely oversized.
  • HandlebarsYour kids should comfortably have a slight bend on their arm while holding the handlebar during the ride. If he over stretches his arms, it is another sign that the bike is only too big.

Which Bike Should I Buy?

The TONY HAWK Dynacraft Park BMX Bikes
The TONY HAWK Dynacraft Park BMX Bikes

No matter what your children’s preference is, make sure the bike is light. This is the most critical factor in deciding a bike for a kid as a heavy one will make it less fun for the little one to ride, not to mention other potential injuries. Every 1kg of children’s bicycles is equal to 10kg of adult bikes. The smile on your champ’s face is priceless, so a happy child equals happy parents.

And try not to save some money and buy a bike that your child could “grow into” down the line. The oversized cycle will no doubt intimidate your son (or daughter) and, even worse, wreck their sense of confidence. Besides, even if it doesn’t, controlling that bike would be challenging, and constant stretching during the ride can wear out the kids quickly. Therefore, there are many manufacturers offering bikes that can share the same growth with your children. These items come with an adjustable frame that can be lengthened to fit the bigger child. This feature will give them a big hand in learning how to ride a bike safely and confidently.


Please note that you are not the one who rides the bike, your children are. Therefore, give them a chance to test out which BMX bike they would want to have. Colorful and fun design might be the other factors that you want to take care of, but be sure it’s just the additional items.