How to install a rear cassette on a bike

What tools will be needed?

To remove a bicycle cassette yourself, it is imperative to have the following list of tools and accessories in your home workshop or in the set of portable spare parts and accessories:

  • bicycle “whip” in the form of a segment of a bicycle chain attached to a handle-lever;
  • 12-slot end puller (or one-piece key-puller) of the cassette retaining ring;
  • if there is only one end puller, then you will also need a 24mm or 27mm spanner (open-end, box), depending on the size of the hex nut on the spline puller.

Replacing the cassette on a bicycle

Experienced cyclists are well aware that a set of rear sprockets of an open multi-speed (sports) bike transmission, the so-called cassette, is actually a consumable unit. Indeed, with intensive high-speed skiing, the teeth of the cassette sprockets wear out quite quickly, and approximately every 1000. 2000 km of run there is a need to replace it with a new one.

install, rear, cassette, bike

Then, how do you replace the cassette on your bike? The first and best option for replacing the cassette on a bicycle is to “take” your bike to a specialized bike workshop, where this operation will be performed as professionally as possible. But, unfortunately, a good professional bicycle service in Ukraine is available only to residents of regional centers, at most, large cities. Also, many avid cyclists and their teams practice long out-of-town “rides”, “move”, during which serious malfunctions of bicycles are frequent, incl. and breakage of the bike transmission cassette. Therefore, any “decent” cycling enthusiast simply needs to have the knowledge and skills of how to remove the stars from the rear wheel on their own.

The procedure for removing the cassette of the rear sprockets of the bicycle

How do I remove the stars from the rear wheel? By and large, for this purpose, simply unscrew the cassette retaining ring, which holds together all the parts of the mechanism. This locking ring has a classic right-hand thread, you can recognize it by the Lock inscription on its surface.

But the trick is that to unscrew this locking ring, you must have a special device (special key). 12 spline puller. In this case, it is necessary to simultaneously keep the cassette sprockets from turning on the bearing. The best for this purpose is a special “tricky” device. a bicycle “whip”.

  • Perform operations to remove the rear bicycle wheel: install the bicycle on the handlebar and saddle, wheels up; unscrew the tightening nuts on the wheel axle (or loosen the eccentric fasteners); remove the chain from the cassette sprockets; remove the wheel from the dropouts, put it on a horizontal platform with the cassette up.
  • Throw a piece of the bicycle whip chain over the large star of the cassette so that the handle of the whip forms a lever that is easy to grip, applying force to the cassette clockwise.
  • Insert the puller into the slots of the cassette retaining ring.
  • Grip the hex of the stripper (24mm or 27mm) with a wrench.
  • Applying opposite forces on the handle of the wrench and on the handle of the whip, it is necessary to turn the retaining ring along the thread. Most likely, you will have to apply considerable effort, as the circlip is usually dirty, “stuck”, and just tightly tightened. Since significant efforts are applied when unscrewing the retaining ring, the use of various handicraft devices and non-specialized universal tools (screwdrivers, pliers, chisels, etc.) for this purpose should be avoided.
  • Unscrew the retaining ring completely, then pull up the cassette and remove it from the splines of the drum (ratchet) of the wheel hub. If the cassette is assembled on a “spider”, it will all pull together as a single unit. If the cassette is assembled on pins, without a “spider”, then, most likely, each sprocket and spacer washer will be removed separately.

How to Install a Cassette | Build a Road Bike #04

Replacing the bike ratchet

It happens that some older sports bikes still have a previous generation rear sprocket assembly called a ratchet. The multi-star ratchet differs from the more modern cassette in that it is screwed (right-hand thread) onto the wheel hub as a whole, with its entire body. Therefore, when dismantling the ratchet, there is no need to keep its sprocket from turning. It is enough to hold the wheel rim with a hand or other fixation, which is incomparably easier.

A special spline puller is also required to remove the multi-star ratchet from the rear wheel. It is similar but not compatible with the cassette remover. The extractor key must be inserted into the corresponding slots on the ratchet cover, and grab the hexagon with a wrench. Applying a force on the wrench counterclockwise, and holding the wheel rim with the other hand from turning, it is necessary to turn the ratchet body along the thread. As with the cassette, this can be tricky and will likely require quite a lot of effort.

Again, the question arises, how to remove the ratchet without a key (puller)? Should again disappoint enthusiasts of a non-standard approach that this technique will most likely fail. In the name of keeping your bike’s drivetrain intact, we strongly recommend purchasing and carrying a dedicated ratchet spline puller. In this case, the operation to dismantle and reassemble it will have a much better chance of success.

Installing the cassette on the bike

The assembly of the system is carried out strictly in the reverse order of removal.

  • Place the cassette base on the hub.
  • The stars are put on alternately with washers if the cassette is collapsible. Blocks or a single piece are attached to the base, depending on the design.
  • After collecting all the elements, screw the retaining ring clockwise using a puller and a wrench.
  • Make sure the mechanism is assembled correctly and replace the bicycle wheel.
  • All bicycle mechanisms need periodic maintenance and there is no need to wait until something breaks down, because technical inspection and proper care can prevent damage. Timely replacement of worn-out parts will help to avoid possible troubles in the future.

    How to remove the sprocket cassette from a bicycle wheel

    When for the first time my cassette was “sharpened” and the teeth began to resemble thorns. I took care of changing the sprockets behind the rear wheel. He took off the wheel, looked at the cassette, did not understand what and where to stick it and how to turn it. But other people’s experience helped me.

    READ  How to choose the right bike for your height

    In general, in order to remove a cassette you need 2 tools (or three). If you take “firmU” from Shimano. then each of these two keys will cost you 25 dollars. The first is actually a piece of chain attached to a metal handle. We pay money exclusively for the brand and “Made in Japan”


    In order to remove the rear sprockets from the bike, you must:

    • Special extractor for the spline nut of the axle;
    • Whip. a metal key with a piece of bicycle chain fixed on it, consisting of 10-20 links;
    • Large adjustable wrench or socket wrench set;
    • Retaining ring puller.

    In addition to these tools, you may need an extension wrench or socket wrench to increase the shoulder and applied force when unscrewing the spline nut.

    Removing the ratchet and cassette

    The rear sprocket block (cassette) is mounted on a ratchet. Maintenance of the cassette is reduced to cleaning it from dirt that gets between the sprockets.

    The device of different cassettes is approximately the same, they differ only in the number of stars (from 5 to 9) and in the way they are attached to each other. On many cassettes, the sprockets are simply tightened with screws.

    In this case, the most worn sprockets can be replaced with new ones. Sometimes a block of sprockets is made non-separable (sprockets are riveted into a single block).

    This increases its strength, but then when some of the sprockets wear out, you will have to change the entire cassette.

    There are various ways of attaching the ratchet cassette to the hub. Modern imported bicycles contain rear hubs with wound ratchets. The body of such a sleeve has a thread on the right side, onto which the ratchet is screwed together with the cassette.

    If you have 7 or less stars, then, most likely, the stars have a ratchet in themselves and to remove them you need a puller to unscrew the entire ratchet as a whole. Actually, there are 7-speed cassettes too, it’s just that a different hub is used for them. with a shorter drum. If the number of stars is 8 or 9, then a cassette hub is usually used and the ratchet is installed on the hub.

    Multiple selection

    Bicycle cassettes can be divided according to the following criteria:

    • material of manufacture;
    • number of stars and their range;
    • compatibility with various types of bicycles;
    • constructions.

    The material for manufacturing can be:

    • Steel is the basic material for most sturdy bike assemblies. Parts made of it are distinguished by an optimal ratio of strength and cost. To protect against corrosion destruction, finished products are chrome-plated. made shiny, nickel-plated. covered with yellow metal, or blued. blackened in oil.
    • Aluminum has the lowest density of all metals. Parts made of its alloys are the lightest, but inferior in strength and service life to steel. Besides, aluminum cassettes are more expensive than steel ones. Anodized aluminum parts are especially popular with fans of reducing bike weight to the maximum. Waitwinners.
    • Titanium, although heavier than aluminum, is lighter than steel. It is strong enough to handle any heavily loaded bike assembly for long periods of time. This material and its alloys do not rust. Minus one. the high cost of products from it. If you do not have a goal to reduce the weight of the bike as much as possible, then it is better to get the most advanced steel cassette for the money that will hold more and last longer.

    The bike cassette can be dialed from a different number of stars:

    • 7. can be seen on older bicycles, the same model years as the ratchet.
    • 8-10. the most common, used today on many bicycles, from mountain to road.
    • 11. by Campagnolo. They can only be installed on the bushings of this company.

    The number of stars and their range is indicated on the cassette label. For example, the inscription “11-36T, 10 speed” means that the smallest star has 11 teeth, the largest has 36 teeth, and there are 10 of them in total.

    The number and range of cassette sprockets determines compatibility with a specific bike type:

    • Mountain. Rear transmission units with 8-10 stars. The smallest should have 11-12, the largest 28-36 teeth.
    • Road racing. Cassettes have the smallest sprockets with 11 teeth and the largest with 22-27 teeth. Campagnolo 11-Star Attachments are only compatible with this type of bike.
    • Urban, cross-country, folding. Devices with the smallest sprocket on 12 teeth and the largest on 27 teeth are suitable.

    There are five types of cassettes according to the type of assembly:

    • Dismountable. Most bike cassettes, except for the smallest two, are riveted or screwed together. This is necessary for the availability of service and assembly. But this design is too heavy and clogged with dirt.
    • On the spider there are some structures assembled on an aluminum frame, which is called a spider. Two smallest stars are riveted to it too. They are famous for their light weight and are excellent for cleaning from dirt.
    • Several spiders bear rare and expensive items, assembled from two parts, 2-3 stars each. Convenient when you need to replace one of the two worn parts, and not replace the entire cassette. As with one spider, they are lighter than common collapsible ones, and they are even easier to clean.
    • OpenGlide is SRAM’s one-piece construction designed exclusively for road bikes. It is held on the splines of the ratchet drum only by a cover at the base of the largest sprocket and an aluminum nut in the smallest sprocket.
    • The X-Dome is the same monolithic device from SRAM, differing only in the way it is mounted on a ratchet. If in the upper part of the small sprocket it is fixed in the same way as the previous structure, then at the base the fastening is the largest star, and not a separate cover. To reduce weight, often the largest locating star is made of aluminum.

    Removing the bike cassette

    Replacing the latest generation Shimano’s Hyperglide bike cassette from the ratchet or rear wheel hub requires two special tools and one common tool.

    • The chain key, which is essential for holding the cassette itself. You need to choose the right one: SR-1 for 10 sprockets, SR-2 for 11 sprockets or less, SR-11, HCW-16.
    • Puller FR series with 12 hooks, because this is how many splines the end clamping nut has, which can be seen in the third figure.
    • 21mm spanner, large adjustable wrench or vice fits. But a 21mm socket wrench is preferable.
    READ  How bike gears work

    One of the FR-1 or FR-5G pullers should loosen the clamping nut. The tool number FR-5G has a guide that makes the work of twisting the nut much easier. Without a guide pin, it is difficult to hold the tool in engagement with one hand when grasping the chain wrench with the other. Using a large ratchet wrench with a set of sockets makes it much more comfortable to hold any puller in place.

    The fourth picture shows the most popular pullers:

    • left FR-1 with 12 long splines on modern Shimano cassettes;
    • right FR-5G with rail for all SRAM / Sachs and most HGs.

    In this picture, you can see that the FR-5G tool is already installed to release the clamped nut.

    The next tool you need is any device to keep the cassette from rotating backwards (counterclockwise) as you release the locked nut. This cannot be done with a large sliding gas wrench, as it tends to bend or scratch the teeth of the sprockets.

    If you do not have a chain wrench or are trying to change a particularly stubborn cassette, you can put a short piece of chain on one of the stars and clamp it in a vice, as shown in the sixth picture.

    The length of the piece of chain and the jaws of the vise is enough to grip the largest star. You don’t have to have a big carpentry vise, no one else has had to twist a nut so tight. It is enough to have a small hanging vise that you can hold in your hand.

    However, the best way to hold the rear cassette is to use a model SR-1 chain wrench or similar, which can be seen in the seventh image from the left.

    By attaching a 12 ” adjustable wrench, a wrench from a set, or even a large 21mm ratchet arm to the FR-5G puller, the socket nut can be loosened.

    While holding the chain whip, turn the adjustable wrench counterclockwise to loosen the jammed nut. She and the little star have notches on their contact surfaces. So you will hear a few clicks when you release the nut.

    How To Change Your Cassette | Road Bike Maintenance

    Loosen a little, remove the chain grip and wrench, and unscrew the clamping ring. As a result, everything should look like in the eighth image.

    Now it is enough to lift the cassette off the ratchet sleeve. But be careful to hold on to the outer two smallest sprockets, because they are not as tightly locked together as the others.

    Remember how each sprocket fits onto the ratchet for later replacement. Note that one of the splines on the ratchet drum has the smallest width and corresponds to a narrow slot on each sprocket in the cassette. All of them should line up in one line. The ratchet after removing the cassette looks like in the ninth image.

    Mostly the ratchet sleeve is made of solid steel. On some road bikes it may have an aluminum outer drum to reduce weight. Once you remove the cassette from such a ratchet, you can notice where dents remain on the soft splines and which sprockets are often loaded. The dented splines, by the way, make the job of removing the cassette very difficult.

    Varieties of cassettes for bicycles and their replacement

    Older bicycles were equipped with an outdated drivetrain assembly called a ratchet. It is screwed on a large diameter thread onto the rear wheel hub. Its ratchet mechanism is not a separate unit and cannot work independently. When the ratchet is removed, everything is twisted at once: the sprockets and the ratchet.

    There is another way to connect the rear sprockets to the wheel. New bicycles are equipped with a more advanced transmission unit. a cassette. If you need to remove it, you can easily separate the set of sprockets and the independent ratchet. All modern bicycles have such an easy-to-maintain unit.

    Internally device

    A bicycle cassette is a pyramid made up of stars of different sizes, which is the node of a high-speed chain drive. The sprockets are separated by an equal distance between themselves by rings or, in some expensive models, by an internal spider frame. Together, all these parts form the body of the device.

    The cassette is mounted on the bike to the drum of the ratchet mechanism along the slots. The ratchet itself in a cylindrical body is attached to the wheel hub with similar hooks. It is the separate cylindrical mechanism on the rear wheel that bursts with a free roll and engages tightly during pedaling. In the cassette, there are no dogs, no cogwheels.

    The cassette body is finally fixed to the rear wheel by an external clamping nut screwed into the internal ratchet mechanism. She and the smallest sprocket have teeth on their mating surfaces to prevent unwinding while riding.

    Installing a cassette

    Replacing the cassette consists in simply lifting it up from the wide splines of the ratchet sleeve and pushing a new set of stars back along the grooves in them.

    Reinstalling the cassette is as easy as removing it. This is essentially the reverse operation. The sprockets should fit snugly on the ratchet splines. It must be remembered that one of the slots is different in width from the others. Be careful. Be careful not to damage the spline flange when putting on the last two small sprockets. Knowing this, it is enough just to put the cassette body (rings and stars) on the ratchet and finally screw the clamping nut along the thread.

    Be careful. Observe the order of installation of the sprockets and spacer rings, which are simply typed onto the splines of the ratchet sleeve one by one. Each spacer ring has two small pins that must fit exactly into the corresponding holes in the sprockets. If this is not done, the sprockets near the ring will be placed too far apart, which will ruin the precise operation of the speed switch.

    You need to tighten the end nut firmly with the same puller and a large wrench. We don’t want the cassette to spin on the road, so it’s a good idea to put the wheel upright and push down on the key lever firmly. But don’t push with your foot! It is recommended to apply a force equal to 21.7–36.2 N ∙ m (about 3 kgf ∙ m). The nut is screwed in clockwise, the ratchet is locked in this direction, so you do not need a chain wrench to install the cassette.

    The lubricant should be used like a tube-type bicycle grease or any other non-lithium, dust-repellent oil.

    After assembling the cassette, make sure that the sprockets do not wobble relative to each other. It is also a good idea to make sure that the distance between them is the same. If everything is correct, then put the wheel on and go for a drive!

    READ  Bicycle Rear Wheel Hub Assembly

    Difference between cassette and ratchet

    What is the difference between a cassette and a ratchet on a bicycle? Many people confuse a ratchet with a bicycle cassette. If you study these parts correctly, then they cannot replace each other. It is very difficult to find a ratchet at this day. Unless you take it off your old bike. On newer and faster bikes, only the cassette can be considered. It is a part that has been improved.

    The disadvantage of the ratchet is that it is not suitable for the axes of a hollow plane whose diameter is 15 millimeters. If we consider the entire mechanism, then the filling of the ratchet consists of dogs. The mechanism of these ratchet parts, on which the outer sleeve is installed (there are sprockets). The nut plays a special role here. This part is the surface for the bearing and also holds all 2 parts. Bearings are installed inside, which consist of identical metal balls.

    The inner bushing. a ratchet particle. is installed on the thread of the wheel, which is located at the back. To remove this detail, you must select a puller by size.

    If you climb a mountain, then there is a large load on the chain and rear wheel. It is with this power that the internal filling of the ratchet must be tightened. Further, through this mechanism, it is tightened along the thread into the wheel hub itself.

    To unscrew the ratchet, which has been tightened for a long time, you need to apply a lot of effort. To do this with a little difficulty, you need tools. These special tools include a wrench (preferably a wrench), a slotted sleeve, and a puller.

    Under no circumstances should the puller be replaced with other tools. They are also not suitable for cassettes. The reason for this is the incompatibility of the splines. A ratchet or cassette on a bicycle most often breaks under heavy loads. Cassette and ratchet. no difference in parsing.

    Bicycle ratchet, why is it needed, similarity to a cassette, how and what to remove, dismantling process

    Cyclists often have to service their vehicle on their own. each time it will be quite expensive to contact specialized repair services. Many bicycle elements can be removed and installed quite easily and simply, but there are details that require the use of specific tools and some knowledge. These include the cassette. a part that is attached to the rear hub.

    How to remove ratchets from a bike?

    The first step is to remove the rear wheel. Next, you need to remove the axle from the hub wheel. Support the wheel firmly against a wall that stands upright. As for the tire, you can, in principle, not remove it. After all, if it is not there, then it will be possible to scratch the wheel rim at the time of repair. It is also much more convenient to work with the tire.

    Next, you need to install a puller and turn it with a key, which is large in size. You need to twist sharply and in jerks, then it is easier to unscrew the ratchet. You cannot turn the puller clockwise, as the bushing is right-hand. It is more convenient to install the key evenly horizontally. Thus, it is convenient and easy to twist and crush.

    To divide the ratchet into two parts for repair, you must definitely take a center punch and a hammer. If you do not have a center punch, then you can take a regular nail or self-tapping screw. The replacement center punch should be as long and large as possible. Further, the ratchet mechanism is disassembled by turning the nut, which is tapered. You need to twist clockwise, since the thread is left-handed.

    “Torpedo” is put on bicycles that are designed for one speed. That is, these are bicycles: children’s, road, folding or for adolescents. Basically, this type of sprocket is installed on modern bicycles. Bushings of this origin have one star. Fasteners are made using splines on cones.

    In case of breakdown, changing the ratchet and cassette on a bicycle is not problematic for a cyclist.


    In order to work with these parts, you need to have special tools. These are:

    • A hammer.
    • A rag that should be tight and lint-free.
    • Thin center punch, for parsing the ratchet.
    • An open-end wrench is needed to unwind the sleeve. The size should be 14-15 millimeters.
    • Non-lithium grease.

    You will also need a puller for a part such as a ratchet. It can be either nut or adjustable. It should be 27 mm. It is best, of course, to use a spanner wrench. This is due to the fact that when scrolling, the key will not jump off the edges.

    What tools are needed to unscrew the cassette and ratchet?

    Different tools are needed for the cassette and ratchet, unfortunately they are not interchangeable.

    To unscrew the ratchet, you just need to have a special puller and a key that this puller will unscrew. My puller looks like this:

    You can read more about how the ratchet is removed and which puller wrench I use here.

    You will need 2 tools to remove the cassette. You will need a special puller for a cassette and a key-whip (I wrote an article on how you can make a whip with your own hands). My tools look like this:

    Cassette Removal & Installation

    Read more about how to shoot a cassette here.

    Easy to install / dismantle cassette and ratchet on the hub

    A positive point for the ratchet is the need for only one tool for dismantling, for this, such a puller with splines and turnkey edges is used.

    In order to install it on the bushing, a tool is not required at all; it is screwed on by hand and retightened during the ride. But to remove it, you will have to sweat, especially if you like to screw it up. You may even need the help of a friend and a large lever on the key.

    But with the cassette, the situation is like this: for installation you need the same puller with slots, and to remove it, you also need a whip.

    But if you have all this, then problems during removal should not arise, and you will not have to apply excessive efforts.

    Bottom line: If quality is your primary concern and your riding style requires reliable parts, you should look towards good branded cassette hubs. And if the bike will be used for light, unhurried walks on flat roads, and you see no reason to spend money on a bike, you can get by with a cheap hub for the same cassette, or a ratchet. But ratchet bushings are definitely the lowest level of reliability.

    Interesting educational video