This article is your guide to work on Shimano and Shimano-compatible 9-speed cassettes (sprocket clusters) -- replacing worn sprockets, making subsitutions, and building custom combinations. The tables below list current models from major brands, and some discontinued models.

Another article on this site gives more general information about cassettes, and on how to upgrade from an older cassette.

In case you're not sure whether your bike has a cassette Freehub or a thread-on freewheel, we have a separate illustrated article explaining how to tell them apart.

Cassettes listed in the table below will fit most Shimano and Shimano-compatible freehub bodies, with the following exceptions:

• Aluminum 10-speed bodies with taller splines work only with 10-speed sprockets
• The narrower 7-speed body would require you to modify the largest sprocket or install only 8 sprockets from a 9-speed cassette or 9 sprockets from a 10-speed cassette. A simpler alternative is to replace the 7-speed cassette body with an 8/9/10-speed body.
• 11-tooth sprockets require a "Hyperglide C" freehub body and lockring.
• The Capreo body has four special sprockets, with 9, 10, 11 and 13 teeth. The other, larger sprockets are standard.

Colored backgrounds in the cells of the tables below identify assemblies of two or more sprockets on a spider to save weight. These sprockets cannot be separated from one another. There's a tradeoff: the more sprockets on a spider, the more you will have to pay for a replacement even if you only wear out one of them! Assemblies of the same sprocket sizes shown in the same background color are compatible with one another, though they may differ in materials and finish. Sprockets on spiders can be replaced by flat steel sprockets with spacers sandwiched between them, and vice versa.

Some Shimano flat steel sprockets and spacers are in bolted or riveted assemblies, indicated by tooth counts in italics in the table. The bolts or rivets only serve to keep sprockets and spacers in order when the cassette is not installed on the freehub. Bolts or rivets can be removed to replace sprockets or build up custom combinations..

Model numbers covered in 2010 Shimano product literature are in boldface, like this: CS‑7700. Older model numbers are included, if verified, in italics, like this: CS‑HG70‑9 and if not, in plain text, like this: CS‑5500.

The ramps and shaped teeth of Shimano Hyperglide sprockets, and their imitations, are designed to improve shifting in the stock progressions, but it is possible to mix and match sprockets with some small penalty in smoothness of shifting. See advice elsewhere on this page.

Individual 9-speed sprockets 16 teeth or smaller are interchangeable between series except that those for a two-tooth jump to the next-larger sprocket have two shifting locations, while those for a one-tooth jump only have one, in a different location.

15T sprocket for one-tooth jump	15T sprocket for two-tooth jump

Many Shimano 9-speed sprocket combinations are identified by two-letter codes such as "ar" or "be". Cassettes with the same code always have the same tooth counts, though they may use different spider or bolted combinations.

SRAM, IRD, Miche and SunRace also offer 9-speed Shimano-compatible cassettes -- see additional sections that follow the Shimano section.

Current parts lists as of 2016

The Shimano parts lists linked below will help you identify models and compare parts.

These links are current on the Shimano site as of March, 2016:

Older parts lists, current as of 2012

The parts lists below are now found in the Internet Archive: Shimano no longer keeps the information available and may not be able to supply replacement parts for some 9-speed cassettes.

IRD has many combinations that are different from Shimano's. Some combinations are rather nice, and others have some uneven steps.

IRD Web page describing 9-speed cassettes with steel sprockets

IRD Web page describing 9-speed cassettes with sprockets on spiders

ES series cassettes have the four largest sprockets on aluminum spiders, two sprockets each. The spiders are indicated by background colors in the table below. The same background color indicates probable compatibility. Alloy cassettes have the two smallest sprockets in steel, the rest CNC machined out of one block of aluminum alloy -- "recommended for racing only" according to the IRD Web site: they will wear out quickly.

Harris Cyclery does not stock IRD cassettes as of this writing. They are included here for the sake of completeness.

Miche makes two cassettes to fit Shimano hubs. Miche also sells individual sprockets in all sizes, useful in building up custom combinations.

Harris Cyclery does not stock Miche cassettes or sprockets as of this writing. They are included here for the sake of completeness.

The sprockets of SRAM combinations which are similar to each other are probably interchangeable while maintaining smooth shifting.

The PG-990 series cassettes use sprockets on a spider. There have been reliability issues reported with the spiders. The XG-999 has 7 sprockets CNC machined from a single block of steel, for light weight. It ain't cheap!.

Harris Cyclery stocks some SRAM cassettes, where they fill gaps in Shimano's offerings.

The links to technical specs are to the Internet Archive. SRAM may no longer stock replacement parts.

SRAM 2008 technical specs listing 9-speed cassettes (see page 34 ff.)
SRAM 2006 technical specs listing 9-speed cassettes (see pages 28-29).

Harris Cyclery does not stock SunRace cassettes as of this writing. They are included here for the sake of completeness.

Because most SunRace cassettes skip the same sprocket sizes, it is fair to assume that the sprockets are interchangeable while maintaining smooth shifting.

The MD7 8-speed cassettes with 9-speed spacing have a chain protector in place of the innermost sprocket, like Shimano Nexave.

Sprockets are steel. The different model numbers with the same sprockets differ in the finish:

MZ7: TI-alloy nitride/Ti Nitride
MX5: Sandblasted satin
M96: Sandblasted satin/ED Black
M96S: Zinc

The catalog listed below is available online only from a source in the Czech Republic, or on our site. The cassettes may not be easy to order.

SunRace 2010-2011 catalog

Shimano wants you to use one of its standard combinations, and offers a wide-enough choice to suit the needs of most cyclists, but you don't have to if you don't want to!

It is not difficult to customize Shimano cassettes. If you substitute an un-approved cog, Uniglide or Hyperglide, SRAM, SunRace, IRD, Miche, or some other brand, it will still work, but the shift to/from that cog will probably not be as smooth as a Hyperglide shift normally is. Since people managed without Hyperglide for several decades, this shouldn't scare you off. In particular, if you substitute the top or bottom sprocket, you will only have one shift that isn't HG; shifts to or from the extreme sprockets tend to be less troublesome than intermediate shifts anyway.

Shimano cassettes that don't use spiders have most of the sprockets held together by 3 small bolts or rivets. These are not essential. Their function is convenience, in allowing the cassette to be installed slightly more easily. To make a custom cassette, you will often need to remove the screws or rivets. Just discard them, they are unnecessary in practice.

• Some cassettes use screws with a 4 mm hex head. These can be removed with an adjustable wrench.
• Some cassettes use screws with a 2 mm Allen head. These are frequently mistaken for rivets.
• The easiest way to remove rivets is to grind off the heads where they protrude from the largest sprocket. I generally do this on a bench grinder.

Harris Cyclery sells some custom cassettes, with sprocket combinations you may find useful:

You might also build up one of your own. Generally, the smallest sprocket needs to be one with a built-in spacer, designed for the top-gear position. While you can't insert or remove a sprocket within a spider module, you can add sprockets on either side of these modules.

For example, if you want a 13-32 9-speed, you can start with a 12-27:

• Replace the 12 and 13 with a top-position 13.
• Add a spacer and a 32 after the 27
  (you don't need to buy the spacer, because you can use the spacer that came between the original flat 13 and the 14.)

7-speed and 8-speed sprockets are slightly wider than 9-speed sprockets, and the spacers are wider too --see spacing cribsheet. Using one or two 7- or 8-speed sprockets in a 9-speed cassette probably won't cause problems, though you might compensate by using narrower spacers next to these sprockets. The smaller sprockets (11, 12, 13) that gve built-in spacers should ideally be matched, but even this isn't generally a problem in practice.

Taking apart stock cassettes is a convenient way to find sprockets to build up your own combination. Miche sells individual sprockets, though they may not be easy to order. The catalog linked below is in Italian...