Curious about BMX bikes? Check out this BMX frame and parts guide to help you understand a little better!
Is it time to dial in your BMX bike with some new parts? Or maybe it’s time to build a custom complete bike of your own? Below you can find a break down of all the different parts you can find on a BMX bike, with a few details about what makes parts unique or what to consider when you’re looking to buy a new frame or part. Most of these parts, we could go on and on about with different styles, geometry, materials, color options and more, so we haven’t gone extremely in-depth. We have also included links to our archives to show you the most recent posts for each style product. Since we try to keep up with most brands newest product releases, you can usually find the newest and most current options available. This BMX frame and parts guide is fairly “brief”, but we have included the important details and links to help you out! We hope you enjoy it.
BMX Frame and Parts Guide
The BMX Frame is the biggest and most important part of your bike. Due to all of the geometry and sizes involved, a frame can make one bike feel completely different from another. The angle of the head tube and seat tube, top tube length, standover height, bottom bracket height, chainstay length and more are all very important details when deciding on the frame that is right for you. Some are designed for street, some for ramps, trails or flatland. Others can be ideal for riding a little bit of everything. It all comes down to the rider and their personal choice on geometry, size, color and more. This is a pretty lengthy subject, so we suggest you check out the BMX Frame Geometry Guide to help you understand what all the angles mean and how they can affect the feel of a bike.
Check out these BMX FRAMES!
The BMX handlebars are another part of the bike that you have plenty of options for when it comes to sizes, geometry, colors and features like 2-piece or 4-piece. Having the right bars can make your bike feel better, allow you to do different tricks easier, have more control and even keep your back or wrists from hurting. Once again, this is a fairly lengthy subject, so we definitely suggest you check out our BMX Handlebar Geometry guide.
Check out these BMX HANDLEBARS!
The BMX Fork is a part on a BMX bike that you have to put a lot of trust in and having the right one is very important. The fork takes a lot of abuse and you don’t want it snapping on you when you’re coming down from a trick. Choosing the fork with the right features for your style of riding is important. The different features like Investment Cast dropouts, offset, taper and butting of the tubing, heat-treating and more are all different things to consider when purchasing a BMX fork. Having a fork you can trust to hold up to everything you throw at it is a must! This is one piece of your bike you won’t want to skimp on to save a few bucks.
Take a look at these BMX FORKS!
Next up on the BMX frame and parts guide… Having the right BMX Stem can also help with the overall look and feel of your bike. Do you prefer top load, front load or a drop down stem? Do you want something that’s sturdy and solid, or are you looking to shave a few ounces with some additional machining? Reach, rise, stack height and more can all adjust the feel of your bike, so knowing what you like is important. These days, a topload stem mixed with a taller set of bars are very popular. Reach and rise can have an overall effect on the way your bike rides and how you fit on the bike. Take into account your height and length of arms when considering a stem. A shorter reach is ideal for people with shorter arms for example. This is one of those personal preference parts because everyone has a different taste in look and feel, so it doesn’t hurt to try out different styles to see what feels best for you if you have the chance. We do recommend avoiding any stem that has a lot of cut outs and too much machining. You put a lot of weight and pressure on a BMX stem and they will break if they are too weak.
Check out all the latest BMX STEMS here!
The difference between a quality BMX bike and a cheaper bike can easily be spotted in the headset. Does your bike use an Integrated head tube with a sealed Integrated headset, or does it use a Standard size head tube with headset cups that need to be pressed in and loose ball bearings? The Integrated head tube and headset are the standard for BMX bikes and there’s a reason why. It’s simple to install and the sealed bearings tend to last a long time if properly maintained. Most integrated headsets available are exactly identical. Some offer different styles of dust caps that can help eliminate spacers or just look cool, but the bearings are for the most part the same. Kink for example offer a headset with titanium nitride coated bearing races and ceramic ball bearings for lighter weight, longer lasting and smoother spinning bearings, but the price is MUCH higher than a regular integrated headset.
Here’s a look at a few BMX HEADSETS!
There are a lot of BMX Grips out there and it all comes down to personal preference. The hardness of the rubber, the design and style, length, flanges or flangeless and colors are all options to consider. Softer grips tend to wear faster, but with improvements in rubber compounds, we’ve seen grip life extended quite a bit. There are a number of different styles, but Mushroom style grips are most common. An example of that style of grip would be the ODI Longneck Grips that have been around for years.
Check out these BMX GRIPS!
When it comes to BMX Pedals, there are a lot of options for riders with plastic, or PC (Polycarbonate), pedals that are usually made from a Nylon blend, or metal, which are usually made from 6065 or 7075 aluminum. A rider will usually choose a pedal based on material, followed by shape, grip, color options and type of bearings (sealed versus unsealed). Plastic pedals tend to be less expensive and a little friendlier on the shins, but they do wear down faster. Plastic pedals usually use unsealed bearings or bushings to help keep the costs down.
Metal pedals offer superior grip and will last you much longer because metal is harder to wear down. Most metal pedals also come with replaceable pins to help extend the life even further. You can also find sealed bearings in some metal BMX pedals, but that does add to the price.
If you like plastic pedals due to the weight and price, but also like the grip of metal pedals, you can also get some plastic pedals with replaceable metal pins. The best of both worlds… Well, except for shinners. Metal pins will always do more damage.
Check out these BMX PEDALS!
Another part that has a lot of options to choose from are BMX Cranks. Traditionally BMX cranks feature a 3-piece design that has two crank arms and a spindle. There are some that utilize a 2-piece or a 2.5-piece design that has one of the arms and spindle attached, eliminating one of the bolts holding the arms on to the spindle. The 2-piece system simplifies the installation process and saves weight, but can prevent you from using Spline Drive sprockets in some cases. BMX cranks are available in three spindle sizes, 19mm, 22mm and 24mm. The larger spindles offer additional strength that are more ideal for street riding because of the heavy landings and harder abuse than somebody like a ramp rider that tends to land smoother with transitions. Most BMX cranks come with a 48-spline spindle, which also allows you to run a Spline Drive BMX sprocket that eliminates the bolt that holds the sprocket in place. BMX cranks also come in a number of sizes, for freestyle 160mm, 165mm, 170mm, 175mm and 180mm are common. You can learn more about how the length of the crank arm effects your bike here Profile Racing – Tech Tip: BMX Crank Arm Size.
Check out these BMX CRANKS!
As we mentioned above with the cranks, BMX Sprockets are available in a number of sizes and styles. The most common sizes of BMX sprockets for freestyle BMX are 25-tooth and 28-tooth, but other sizes are also available. BMX sprockets usually come with a 24mm bore, with 19mm and 22mm adaptors to fit the different BMX crank spindle sizes. There are three styles of sprocket holes; standard which requires a bolt to hold the sprocket to the crank arm, Spline Drive which allows the sprocket to slide onto the 48-spline spindle, holding the sprocket in place and eliminating the bolt and Socket drive, which is similar to Spline Drive but uses a hexagon shape to hold the spindle on the cranks. Socket Drive is not as common as the other two styles. Another thing to consider with BMX Sprockets are if you want a guard or not to protect the chain from grinding. There are three styles of sprockets; no guard, which is the lightest option that leave the teeth exposed, full guard which features a guard that wraps around the entire sprocket protecting the teeth and half-guard which uses a removable guard that only covers a portion of the sprocket saving weight. The full guard is usually integrated with the sprocket, but some do come with a removable guard as well.
Take a look at these BMX SPROCKETS!
The BMX Chain is another part that you will want to invest in quality because cheaper chains tend to break more frequently and that usually leads to crashing and smashing your knee into your stem. The standard BMX chain comes in a 1/8″ size with full size and half-link styles. Some riders swear by half-link chains like The Shadow Conspiracy’s Interlock chain (seen above) and others believe full-link chains are stronger. The biggest benefit to half-link chains is the adjustability that you have in the dropouts on your frame, allowing you to find the perfect spot for your wheel. They also tend to work better on the tight 25-9 gear ratio. Many full-size chains also come with a single half-link pre-installed to also give you that adjustability. Things like thicker side plates and heat-treated pins can greatly improve the overall strength of a BMX chain. You get what you pay for when it comes to BMX chains for the most part.
Check out these BMX CHAINS!
When it comes to BMX seats you have plenty of options for styles and sizes. There are four main styles of BMX seats; Pivotal, Tripod, Combo and Railed. The Pivotal style seat comes in two versions as well; regular where the bolt comes in through the top, or Stealth which brings the bolt in through the bottom giving you a cleaner look up top. Pivotal seats offer more adjustability in angle with multiple teeth allowing you to set your seat to an angle most comfortable to you. The Tripod seat is simplified and lightweight using one small bolt to hold the seat in place. The downside to Tripod is that it offers only two angles. Combo seats are a seat and post all in one, which offers only one angle since everything is one piece. Railed seats aren’t as common these days due to weight and complexity of installation. The railed seat does offer the most adjustability allowing you to adjust the angle of the seat up and down, and move the seat forward and backwards. BMX seats also come in slim, Mid and Fat versions for padding. You can find many colors, styles and materials used on BMX seats from leather to fabric and Kevlar.
Check out these BMX SEATS!
BMX Seat Post
Like we mentioned above with BMX seats, there are also four styes of BMX seat posts to match the seats. There are the Pivotal posts with small teeth, Tripod with two hooks and a bolt hole, combo which the post and seat are combined and railed which uses a clamping system to pinch the rails of the seat in place. There is also the Stealth Pivotal seat posts that use the Pivotal style seat, but bolt into place from below.
Check out these BMX SEAT POSTS
BMX Seat Post Clamp
The final piece to BMX seats, the BMX Seat Post Clamp which holds the seat post at your designated height and the seat straight forward. Seat post clamps are commonly found built in, or “Integrated” with BMX frames, eliminating the need for a separate clamp. Some BMX frames do not come with a seat post clamp built-in to help keep the overall price of the frame down, so you will need a clamp in that case.
Check out these BMX SEAT POST CLAMPS!
When it comes to BMX tires you have plenty of options to choose from. There are smoother tires that are ideal for street riding all the way to knobby, aggressive tires that are more for trails and everything in between. Add in multiple sizes of width from 1.95″ to 2.40″, PSI ratings from 60 to 120, TPI ratings, wire bead and Kevlar bead, price ranges and colors galore… It can get a little tricky on figuring out just what tire is right for you.
Street riders typically choose a smoother tread pattern with a wider width for less rolling resistance and more impact absorption from the “cushiony” surface area. Street tires typically have a higher TPI (Threads Per Inch) rating because it makes for a more flexible tire that helps to resist pinch flats and punctures.
Ramp riders typically go with a smooth, but narrower tire with a higher PSI rating. The reason for this is because it has less rolling resistance and they are typically trying to get the most speed out of pumping over pedaling, so the harder, narrower tires help keep the momentum going. You can find a lot of ramp specific tires having a Kevlar or “Folding” bead because of the weight savings.
When it comes to trails, you’re generally looking at a more aggressive, knobbier tire that is built to give you plenty of traction. These tires typically have a lower TPI rating to give the tire a sturdier build and can resist punctures from larger objects you might come in contact with like logs or logs. With that comes a lower PSI rating. Typically dirt tires have a lower, 65 PSI rating.
However, with so many riders riding a little bit of everything, there are a number of tires available that balance out all of the features so it can hold up to everything you choose to ride. Tires with a smoother center tread and more aggressive sides, higher TPI and PSI ratings and a wire bead are common features for tires that are designed for all around use.
View: BMX TIRES
Another part of your BMX bike that has endless possibilities or options would be BMX Hubs. The hubs are the centerpiece to your wheels that keep you rolling. They range in price and features quite a bit.
Front Hubs are typically smaller and utilize three key pieces; the hub shell, bearings and axle. Front hub shells are smaller because typically they take less abuse than the rear hubs and require less internals. You can typically find a 3/8″ axle on front hubs because they aren’t taking as much of the impact as the rear wheel. Axles are available in “male” or “female” styles. The Male axles feature a longer axle with threads on the outside that you thread an axle nut onto. Your dropouts sit on the axle. Female axles feature a center axle inside the hub shell, with two male bolts that are screwed into the center axle. Your dropouts sit on the bolts. Most front hubs also come with sealed bearings. We would suggest avoiding any hubs with unsealed bearings because they tend to wear out quicker and require more maintenance. The vast majority of front hubs are available in 36 spoke styles. You can find 48-spoke options, but it’s pretty unnecessary unless you’re dropping off roofs and huge gaps like Sean Burns.
Rear hubs are available in two main styles; cassette and freecoaster. The biggest difference between these two styles of hubs are that cassette hubs require you to pedal backwards when going fakie, where a freecoaster allows you to disengage the driver to coast backwards without having to pedal. Cassette hubs tend to be more reliable, require less maintenance and have quicker engagement when you pedal. Freecoasters allow you to disengage the hub by simply backpedaling. The amount the cranks need to turn can be adjusted, which is called slack. Most freecoaster hubs use slack washers that you can add or remove to change the amount of movement needed to engage or disengage the hub. The downside is the majority of the freecoaster hubs require you to take them apart to make adjustments, they are also heavier due to the components found inside the hub shell like the clutch and washers that you don’t find on a cassette hub.
Both styles of hubs use Drivers which is essentially the small sprocket in the drive line. Most hubs use a 9-tooth or 10-tooth driver. There are different styles of hubs that use Freewheels with larger teeth. These are usually found on race bikes that benefit from larger gearing. The vast majority of rear hubs are available in 36-spoke style. You can find 48-spoke options, but it’s pretty unnecessary unless you’re dropping off roofs and huge gaps like we mentioned on the front hubs. Most hubs also come with sealed bearings, which we highly recommend.
Hubs are highly customizable as well. You can use female or male axles, chromoly, aluminum and titanium metal for axles, bolts, washers, cones and drivers and there are countless color options.
View: BMX HUBS
When it comes to BMX rims, there are plenty of options. The key factors that differentiate rims are the number of walls, design, width and height. Most BMX rims are available in a “double-wall” which means the rims are structured with two braces inside the rim to help withstand the abuse from impacts. Single wall rims are typically found on entry level complete bikes and tend to bend easily. Triple wall rims were more common in the late 90’s / early 2000’s but pretty overkill. With the level of quality and innovation, double wall will hold up to the majority of riders needs. The way the rim is designed can affect the shape, weight and strength which is why you can find a range of styles and weights on double wall rims. A wider rim with shorter sidewalls will generally be stronger than a narrower rim with taller sidewalls because it can handle side and direct impacts better.
Another factor to consider is if you are brakeless or run brakes. Some BMX rims are designed for brakeless riders with an angled sidewall or a color coating that is not ideal for brakes. If you run brakes, chrome tends to be the best braking surface.
You can find most 20″ BMX rims in 36-hole, double wall and endless color options. Black and Chrome being the two most common options.
View: BMX RIMS
Similar to BMX pedals, there is a lot of personal preference when it comes to BMX Pegs. Metal Pegs are typically made from chromoly or aluminum. Plastic pegs are typically made with a aluminum or steel core with nylon composite sleeves that are replaceable.
Things to consider with the pegs are length and diameter. Most pegs are in the 4″ range, but can be a little longer. The diameter is usually around 34mm, but can be thicker when it comes to plastic pegs since the sleeves can add to that. Another is that plastic pegs tend to grind better, but they can break and wear out much faster than metal pegs. Metal are more cost effective because they will last you much longer.
View: BMX PEGS
BMX Hub Guard
If you’re planning on running pegs, it’s highly advised that you pick up some Hub Guards. If you aren’t running them, you will find that your hubs and spokes will get worn down and break after you have been grinding. Hub guards are very common these days and virtually every hub has a plastic or metal option. Once again, it’s personal preference if you want to run plastic or metal. Plastic tend to help you with grinds where metal will last you longer. Hub guards are designed for front and rear hubs, drive and non-drive side so you can run one over your chain if you happen to grind on both sides. It’s best to stick to the same hub guard brand as your hub because they are designed to be used with them, but many are universal to fit multiple styles and brands hubs.
View: BMX HUB GUARDS
Although they aren’t as common as they used to be, BMX brakes are still a great addition to any bike because they not only make riding safer with the ability to easily stop, but they can open up the opportunity for many different tricks that you might not be able to do, or be able to do as easily, without brakes. The downside to brakes is that they can be a little tricky to work with because they usually require a little bit of maintenance to keep them dialed in. Brakes usually come with arms that have two springs that can be adjusted on each arm to control the tension and distance the pad is from the rim. This is a bit of a fine art to master. Once you understand it, it gets a lot easier to adjust and maintain brakes. Here’s a How To Install and Adjust BMX Brakes video. Luckily, brands like Odyssey and Flybikes also offer brakes that eliminate the springs in the arms and use a bridge spring or a small spring to control the tension and arms. This makes installation a breeze, but does require your wheel to be straight in the dropouts and your rim to be true. Beyond that, having a straight cable, gyro or even front brakes are different options to choose from. If you like tailwhips and barspins, you would most likely want to run a gyro or detangler. If you aren’t doing that or like simplicity, a straight cable should do the trick. Also note that front brakes require a fork with front brake mounts or a separate plate that enables you to run brakes, and you will want brakes designed for the front since they work a little different. Along with brakes come brake cables, a gyro / detangler and brake levers. So it does add a few more components to the bike, but it has its benefits when installed and dialed in properly.
View: BMX Brakes
Complete BMX Bikes
If you aren’t into building up your own bike, or you want to save a little money, you could always go the complete bike route! Complete BMX bikes have improved greatly and continue to improve every year. There are a number of higher end complete bikes that have full chromoly frames and are loaded up with after market parts, making it similar to a custom build. All the bike with a fraction of the price!
Check out these BMX Bikes!
Customize your own bike in our BMX Color App!
That wraps up the BMX Frame and Parts Guide. We hope it helped you out and got you on the path to dialing in a new bike or at least updating and improving your current bike!