List of a Mountain Bike Parts – Guide to Important Parts and Components
If mountain biking is something that you have only just become involved with, it may be helpful to understand what the basic parts of a mountain bike are. Obviously, a mountain bike is made up from hundreds of parts ranging from washers to the frame itself. To keep things simple, we have limited our guide to a few of the major components that make up your mountain bike.
This guide to mountain bike is here to assist you in getting to know your MTB parts whilst trying to avoid jargon. There is no need to memorize all of this at once, as you can come back to this article and refresh your memory about these bike components at any stage.
Parts of a Mountain Bike
The first of the bike components that we will look at is the frame. The frame consists of two triangles. First, we can see that the front triangle is comprised of the seat tube, down tube, top tube, and head tube. Look at your bike and you will easily identify which is which. The head tube is located right at the front of the frame and this is where the cockpit components and the front fork components meet.
The rear triangle comprises of the seat tube already mentioned and seats stay which runs off the seat tube towards the back hub. The chain stay runs parallel to the chain.
Frame Sizes for the height of the rider
- If rider is 5’6” to 5’10” tall – 17” to 18” frame
- Rider is 5’10” to 6’1” tall – 19” to 20” frame
- Rider is 6’1” to 6’4” tall – 21” to 22” frame
Modern bicycle frames are usually constructed from steel, aluminum, titanium and carbon fiber and these materials will have variable costs. However, it is possible that the bicycle made of the cheapest material might still be a more comfortable and fats ride than one of the most expensive, because of differences in the frame shape and other design factors.
The handlebars and all the components attached to them are called the cockpit. Typically, the components are the back brake lever and rear shifter. These are located near the right-hand grip. You will also find the front brake lever and front shifter (if there is one) near the left grip. In Europe, these sides may be reversed.
The handlebars are often way down the list of factors considered when buying a mountain bike. Handlebars do have different properties that can affect your ride. If your riding position feels too low then buying a riser handlebar can correct your position to a more comfortable one. In order to make it possible to change components, the diameter of the handlebar at the grip is always going to be 22.2mm.
However, the diameter at the stem may be one of three differing diameters. 25.4 mm, 31.8mm, and 35mm. The most common at the moment is 31.8mm. Why should you care? If you want to change your handlebar without having to change your stem then it is important to choose a handlebar with the same clamp diameter.
Brake levers are fixed to the handlebars. There are two types of brake lever:
- Standard Pull – designed for caliper brakes (typically found on BMX or road bikes).
- Long Pull – These are for direct-pull cantilever brakes (often found on mountain bikes).
The handlebars are connected to the front fork by the stem. The stem links the handlebars to the steerer tube, which is pushed through the head tube.
The headset provides an interface between the head tube and the front fork. The headset will usually comprise of two cups placed on the head tube that contain ball bearings and provide a friction-less connection between the front fork and the head tube.
Fork and Shock Absorbers / Suspension Systems
The front fork will probably have a front suspension made up of two shock-absorbing tubes. The shock absorbers make riding on rough terrain more comfortable. The fork will connect to the front wheel.
Some mountain bikes will come with just front suspension fitted. These are called Hard tail. Those fitted with front and rear suspension are called full-suspension or dual suspension. Even if no suspension is fitted the designers of mountain bikes will have created them in such a way that the actual frame will have some give and absorb some of the impacts.
Mountain bike grips are attached to the MTB’s handlebar and one of the contact points on the bike. Commonly this is made of soft and durable rubber.
The mountain bike rims are made from the exclusively-designed wire-spoke system, made of light-weight and sturdy materials mainly for off-road riding. These rims are attached to the mountain bike’s frame and fork. There are different sizes of mountain bike rims but the most common size of it is 26-inch.
The front wheel is made up of the hub, spokes, and rim. The front wheel is connected to the front fork by either a quick-release skewer or a thru-axle. The hub is the center of the wheel and from the hub; the spokes radiate and connect to the rim. The rim is covered with a tire.
The first wheel that was created with wire spokes to absorb tension was way back in 1853.
- The Hub is the center of the wheel and is made up of the axle, bearings, and a hub shell.
- The axle is usually attached to the fork with a quick release which allows the removal and fitting of the wheel without tools. Older hubs featured a nut.
The three varieties of mountain bike will all have different tire widths:
- Trail & mountain bikes – 2.25” to 2.4” (most regular bikes)
- Downhill bikes – up to 2.5” (to cope with big drops and rocky areas)
- Fat bikes – 3.7” to 5” (all-season trail work)
The shifter is the small device placed on the handlebar, next to the MTB grips, close to the brake lever. This device is connected to the derailleur with a cable that shifts the chain to all the bikes cogs or chain rings. It can be in the form of thumb shifter, rapid fire shifter, or grip shifter.
The saddle is fixed to the seat post which is inserted into the bike frame seat tube. There are five types of saddle:
- General mountain bike saddle – Nose is slimmer and downward sloping, the rear is more shaped.
- Racing Saddle – Very narrow saddle designed to reduce rubbing.Very little padding if any.
- Gel Saddles – Built for comfort has a gel layer between the seat and the rider that moves with him.
- Noseless – Not very common. As the name suggests is missing the traditional saddle nose.
Don’t forget to add a saddle bag while you go out for a long ride.
The seat post is inserted into the seat tube and connects the saddle to the seat tube. Recent innovation is dropper post which can be adjusted while moving through the use of the lever on the handlebars.
A pedal is connected to the crankset through a spindle with ball bearings on the end that sit between the pedal and spindle. This allows the pedal to remain in line with the foot.
There are two types of pedals, clip-in, and flat pedals. clip-in pedals require the user to attach a cleat to the sole of their shoe which clicks into place on the pedal. Flat pedals are just simple pedals that you place your foot on and then you are off.
The crankset is the component that converts the motion from the cyclist’s legs to a rotating motion used to drive the chain. The crankset will be made up of one or more sprockets. These are attached to the frame by the bottom bracket and connected to the pedals.
The roller chain connects the sprockets on the chainset to the drive wheel rear wheel on the bike). Most chains are made of plain carbon or alloy steel. Gearing via the various sizes of sprockets is used to optimize the power of the pedaling., and example of which is the Derailleur gears.
Chains have a limited life and eventually will need replacing. A symptom of a chain that is nearing the end of its life is one that has stretched and as a result, occasionally it misses the correct positioning on the sprocket.
Check our review of the best mountain bike chains.
A Mountain bike fork is the part of the MTB that holds its front wheel; it also lets the biker control as well as balance the MTB. It has a shock-absorber that can either be spring suspension or air suspension.
Derailleur Gears are a transmission system built around variable-sized sprockets that attach to the crankset. Front and rear derailers are constructed around a chain guide that switches the chain between sprockets. Sometimes only the rear derailleur is fitted. The chain guide is moved through a Bowden cable that connects to a shifter on the handlebars.
There are four types of shifter:
- Grip shifter – a wheel that is rotated to select the desired gear.
- Trigger shifter – A lever is pulled or pushed
- Thum shifter – similar to above
- Road bike shifter – the shifter is merged with the brake lever… This is sometimes referred to as a Brifter.
There are three types of brakes:
- Rim Brakes – Friction pads mounted adjacent to the rim of the wheel, made of rubber, leather, or cork. Mounted in metal shoes
- Disc Brakes – Metal disc or rotor connected to the wheel hub. Pads are pushed against the disc brake to slow or stop the bicycle
- Drum Brakes – Similar to a car two pads are pushed outwards against a surface-mounted inside the hub.
I hope that you have found this simple explanation of the components that make up a mountain bike helpful. I have tried to keep it free of jargon. Knowing the correct term for components will make it easier if you ever have to replace a part in the future.
Brake levers are particularly susceptible to damage in crashes, for example. I have deliberately ignored components that are being phased out of modern bicycles and also included features that are just starting to appear in newer designs, like the dropper post that allows you to adjust the seat height while you are still moving.