How-To’s – BMX Time

Are you wondering what BMX bike you should get for yourself or your kids? Perfect timing! We'll cover every aspect of it here. The best option for a BMX Bike will come out of the mix of your height, weight, expertise level, riding style, and budget. Defining those items will lead you to choose the right BMX bike. We'll go over each of the aspects outlined above in detail in order to arrive at the best possible conclusion. What BMX Bike Size Should You Get? The BMX bike size that you should get can be deduced from your height, as that's what establishes the appropriate length for the top tube of the frame, which in turn determines the bike size. BMX bike sizes come from "micro" (smallest) to "pro XXL" (biggest). Check where your height fits in the table below and you'll get the answer for the appropriate BMX bike size for you. Rider HeightTop Tube LengthFrame SizeWheels Size4'4" & under15" - 16.5"Micro12"-14"4'4" - 4'10"16" - 17.5"Mini16"-184'6" - 5'1"17" - 18.5"Junior20"5'1" - 5'4"18.5" - 19.5"Expert20"5'2" - 5'6"19.25" - 20"Expert XL20"5'3" - 5'8"20" - 20.5"Pro20"5'7" - 6'0"20.75" - 21.25"Pro XL20"6' & over21.25" - 22"Pro XXL20" The size of the wheels is something relative, but basically, the smallest bikes, meant as the first BMX bike for toddlers, come with 12" wheels. Then, for kids between 5 - 8 years old, 16" wheels will probably be more suitable. The next step is the standard 20" wheel. Define Your Intentions: Where Do You Want To Ride? It's important to define what type of riding you want the bike for as that will lead you into different dimensions, geometries, components, and materials. There are many things you can do with your bike, but mainly you will use it for either racing or freestyle (performing tricks in skateparks, on the street, on dirt jumps, or flatland). It's not that you're not going to be allowed to ride on a park if you have a racing bike or on a track if you have a freestyle bike, but there are variations between these two types of bikes that -though they may look or seem small- can make a huge difference in the riding experience. BMX Racing Bike vs. Freestyle The main differences between BMX racing and freestyle bikes are that for racing they're created for speed and acceleration (light materials and large sprocket) whereas for freestyle they're built to be robust to withstand the abuse of hard landings and versatile to be easily maneuverable (resistant materials and special components like detanglers and pegs). Let's define each one of the different BMX specialties: Park/Vert When we talk about 'park' we basically mean skateparks, where you find several types of ramps and bowls. A 'vert' is a vertical ramp, normally a half-pipe ramps 10-feet tall facing each other. If this is what you want to do, you need to have a pretty strong bike, solid enough to withstand big landings. It should have at least 36 spokes to make the wheel strong and a thick tire to provide a good grip and also to better absorb the impacts. Street Street is about doing tricks using all kinds of obstacles you can find in the street, such as handrails, stairs, ledges, benches, and so on. This bike should also be stiff enough to withstand severe abuse. Street riders use pegs on their axles for grindings and landings and most of them run a detangler to do barspins without being interfered with by the brakes' cables. Dirt Jumping It's about jumping between huge dirt ramps and doing air tricks. This style evolved directly from BMX track racing. The type of bike sued for dirt jumping is quite similar to the ones above, however, it usually has knobbier heavily treaded tires to provide better grip when taking off and landing. Flatland Flatland is about platforming tricks on a small flat area, trying to maintain your balance while using the bike as a partner for the tricks. It's also known as breakdancing on a bike. Flatland bikes feature a smaller frame, with a shorter seat post. It also has shorter crank arms. All this with the purpose of providing more clearance for moving around the bike. Racing Racing is where BMX started, 50 years ago. Races take place in tracks full of rollers, banked turns, and jumps. The first rider that crosses the finish line is the winner. The racing bike has light parts, slimmer tires for less contact with the ground, and a large sprocket to provide good pedaling power. Each feature of a racing bike favors speed and acceleration. Cruiser Cruiser isn't exactly a specialty. Any type of BMX bike with wheels larger than 20" is called a 'cruiser'. Most commonly, 24" wheeled bikes. These are great for racing, dirt jumping, and for longer rides like commuting. Many BMX racing competitions have a Cruiser category, including the World Championships. BMX Bike Parts & Features We'll take a quick look at the main parts of the BMX bike, just so you have it as a reference. Materials The materials outlined here refer to the most convenient for each specialty and the most preferred by the advanced/pro riders. However, this doesn't mean that, for example, all race bikes in the market come with aluminum parts. Obviously, it all depends on the price. The material of choice for making BMX bikes is, of course, steel. Now there are several types of steel. Most entry-level bikes are made of hi-tensile (or 'hi-ten') steel, which is probably the cheapest option. It's not as durable as other alternatives, but it can definitely be a good option for a first experimental BMX bike. There are some types of alloys on the market from which Chromolly is the most popular for BMX freestyle bikes and beginners' racing bikes. Chromoly is a great option, as it is lighter and stiffer than regular hi-ten while being affordable. It's not as light as aluminum, but it's strong enough to withstand the abuse of hard landings and grindings. Aluminum is what advanced level racing bikes are made of. Racing is all about speed and aluminum fits perfectly in the equation for being lighter than Chromolly and resistant when absorbing the typical landings on a race. Now let's put all this info above into a table to have a better picture of which type of bike and components are more suitable for each BMX specialty. BMX SpecialtyBike Features- Park- Vert- Street- Dirt Jumping- Material: Chromolly- Frame: Medium- Brakes: Rear U-brake (recommended: detangler)- Sprocket: Small- Crank arms: Medium- Tires: Wide- Flatland- Material: Chromolly- Frame: Small- Brakes: Front and rear U-brake (recommended: detangler)- Sprocket: Small- Crank arms: Short- Tires: As preferred by the rider- Racing- Material: Aluminum- Frame: Large- Brakes: Front and rear U-brake(mounts on the outside of the seatstay) - Sprocket: Large- Crank arms: Long- Tires: Thin What's Your Budget? Your budget will have the last word here, right? So let's see what type of bike we can find based on the price ranges below: $100-$400: Kids/Youth/Beginner BMX Bikes Yes, there are bikes for around $100. Most of the bikes in this category are kids' bikes. They are cheap for two main reasons: less raw material utilized and cheap materials. If you're looking for a kids' bike, you don't need to go any further. Although you could find more expensive kids bikes, it'll be for initiating kids into BMX, so what's the point? Bikes in this range generally feature hi-ten steel, basic bearings, single-walled rims, and poor weldings. For adults' bikes, I recommend stepping up to the next range if possible. However, there are some cool beginner bikes than can be found for $350-$400 $400-$800: Intermediate BMX Bikes The main feature of this range is probably the material: chromoly. As we've seen above, it is the standard and most reliable material for freestyle bikes. This range also offers sealed bearings, a detangler for the brakes, two or three-piece cranks, and maybe pegs to make it more appealing. This is a great range to be looking into if you already have some experience and you definitely know your riding preferences. By now, you might have already broken some parts practicing your first tricks, so now you have a better idea of what's all this about and you can go for a stronger and lighter bike. $800 - Infinity: Advanced/Pro Level BMX Bikes These are the top-level bikes. Best materials for all of the components. They come with sealed bearings in the hubs, bottom bracket, and headset, stronger rims, and lighter hubs. The bikes on this range will often be custom built. They're assembled and built on the shops, adding each part separately. Talking about budget, the sky's the limit. Custom BMX Bike: Create Your Own Model So far we've seen how to choose the best complete BMX bike for you. But you also have the option of creating your own bike from scratch, selecting each component one by one based on your budget, style, and preferences. If you decide to take this route, all the info we've just seen will help you with your decisions. In addition, I'd like to go into some details regarding some of the parts. Tires The tires are obviously the most important point of contact of the bike with the ground, thus, the tire choice affects speed and grip. The best option for dirt jumping is to have more tread to gain more traction. Wide and low-pressure tires for more surface and more contact area to provide a better grip. For street and park normally a tire with medium tread or smooth is the standard choice. Preferably a wide tire with good pressure to protect the rims when landing. Race tires are slim, for less contact with the ground and to save some weight, favoring speed. For flatland, speed, grip, and traction are important but not fundamental aspects of the riding, meaning there are no established rules. So the tire choice is up to each rider's style and preference. Hubs The hub is the center part of the wheels, both front, and rear. They are connected to the rims by the spokes and axle. The part that allows the hub to spin freely is the bearing. Sealed bearings are much stronger and the best option. You must make sure the hub shells' holes match the number of spokes you have. The rear hub is a very important part of the drive train. There are three types of BMX hubs: cassette, freecoaster, and freewheel. Cassette. It's the most popular choice for BMX bikes in both freestyle and race. It's an internal mechanism that provides instant pedaling. With a cassette hub when you go backward you also have to pedal backward. Freecoaster. A freecoaster, like its name suggests, allows you to go backward without pedaling. Unlike the cassette, it doesn't provide instant pedal engagement. It takes a little pedaling before you get the engagement. This is called 'slack' and its variance can be adjusted from inside the hub.Freewheel. It's an external piece that's threaded onto the hub. Freewheels used to be very common but were eclipsed by the new technology of cassettes and freecoasters. Rims 32mm is the standard width for BMX freestyle bikes rims. If you're going to put your wheels through a lot of abuse you can opt for 36mm rims. The best rims are made of aluminum. They have multiple walls for extra stiffness, double wall being the ideal standard for most riders. Some rims are drilled in order to save some weight. When selecting a rim you must be sure that its spoke holes count matches the number of spokes you need. Spokes The number of spokes you prefer is something fundamental to take into account when buying a new bike, rim, or wheel. 36 is the standard number of spokes most riders prefer on a freestyle bike. However, 48 spokes might be your best option if you're a heavy guy. Racing wheels can have 28 spokes and alloy rims in order to save some weight. Gearing When choosing a sprocket you must consider the 'gear ratio' which is the ideal combination of the number of teeth in both sprocket and driver or cog (hub sprocket). The gear ratio is obtained by dividing the number of teeth on the sprocket by the number on the driver. Example 44 / 16 = 2.75. This means that the rear wheel will rollover 2.75 times for every rotation of the sprocket. The lower the number, the easier is it to pedal; the higher the number, the more force it requires to pedal. In order to provide more clearance for tricks and stunts, freestyle bikes come with small sprocket/driver combination. This combo also provides good reaction power, meaning that the bike can react faster. Racing bikes have large sprockets to allow the riders to generate explosive power and go fast. The larger the sprocket, the faster you can go. Conclusion Whether if it's your first time or not, buying a BMX bike is always a memorable moment. I hope all the info we've just been through helps you to make the right decisions about the size of the bike and how to pick a complete or build a custom bike based on your riding preference, style, and budget. Related Articles Best BMX Pedals (Plastic/Metal)The World Of BMX Brakes (And NO Brakes)How To Make Your BMX Bike Lighter: A Full Guide Photo credits: [Bike image: by Andrraw / Wikimedia / Creative Commons License / Modifications: Added bike parts names.]