This article will explain bicycle cassette compatibility i.e. what cassettes can be mixed with which rear shifters/derailleurs. For compatibility with various chains, see the chain compatibility article. Overview of compatibility and possible combinations will be given according to the number of sprockets. From the old 6 sprocket standard to the newest 12 sprocket one. There are two things to consider when combining cassettes: number of sprockets, and sprocket spacing. Both those things affect the cassette width and indexing of shifters. Table with sprocket thickness and spacing is at the end of this post.
Before you start, to avoid any misunderstanding:
please take the 5 minutes needed to read the compatibility articles use instructions.
Related article: Speeds – rear sprockets.
Indexed shifters work with clicks – each click changes one “speed”. In order to function properly, they require that derailleur movement ratio and sprocket widths are matched with shifter’s cable pull ratio. This is explained in detail in a separate article on shifters: Rear shifter compatibility.
One more thing before explaining compatibility: there are two main standards of cassette mounting. Freewheel and freehub. That is explained in the article: Freewheel vs cassette. 6 speed is always with a freewheel. 8 and more speeds is always a freehub cassette (there used to be 8 speed freewheels, but those where never widespread and are now obsolete). 7 speeds usually come as freewheel cassettes, but can also be found in a freehub cassette standard.
Most manufacturers’ cassettes (and freehub body splines) are compatible with Shimano (SRAM, Sun Race etc.), while Campagnolo cassettes use different freehub splines – that is explained on. Also, SRAM XD cassettes (and freehub body splines) differ from all the rest. All this is explained in Rear hub compatibility post. These mounting standards are important for physical mounting of the cassette on the wheel, they have nothing to do with chain and shifter/derailleur compatibility.
6 speeds
All the 6 speed sprockets are with a freewheel. As a rule of thumb, all the models of all the manufacturers can be interchanged without problems. Shimano’s standard is widely accepted, though you might come accross an “exotic” model with narrower sprockets, more narrowly packed.
Sprockets are placed at 5 to 5.5 mm spacing, with each sprocket being 1.85 to 2 mm thick (depending on the model).
7 speeds freewheel
Sprocket width and spacing is the same as for some 6 speed systems. Here, Shimano standard is widely accepted and all the manufacturers’ 7 speed freewheels are compatible with it.
Sprockets are placed at 5 mm spacing, with each sprocket being 1.85 mm thick.
7 speed freehub (cassette)
There is an obsolete Shimano Uniglide standard, and a current, Shimano Hyperglide standard. If for any reason you have a Shimano Uniglide cassette, they can be fitted onto a Hyperglide freehub, just the smallest sprocket needs to be replaced with a Hyperglide one.
Uniglide uses threaded smallest sprocket to hold the cassette in place, while the Hyperglide uses a special lockring.
To the right are two Hyperglide sprockets (bottom smallest, top 2nd smallest)
Front part of the smallest Hyperglide sprocket has small teeth to hold the lockring in place.
All the modern cassettes are of Hyperglide standard, regardless of the teeth number. In case of having a uniglide freehub, mounting a modern (available) hyperglide cassette can be done in two solutions. One is to remove smallest sprocket off the (new) hyperglide cassette and use the (worn) smallest uniglide sprocket as a lockring, filing/grinding off the widest spline of the rest of the (new) hyperglide sprockets. More complicated (probably better) solution is to switch the freehub body for a hyperglide one. Video explaining it is here: converting an uniglide freehub to a hyperglide.
This goes for 8 speed as well: 7 speed cassettes have the same sprocket width as 6 and 8 speeds, but 8 speed is a bit tighter spaced – at 4.8 mm. This means that 8 speed sprockets can be used for 7 speed cassettes, as long as the 7 speed spacers between sprockets are used.
Many cassettes have sprockets held together with 3 small rivets, but these are only for convenience when mounting and can be removed so that sprockets can be swapped.
8 speeds
The same sprocket width as with 6 and 7 speeds, but a bit tighter spaced – at 4.8 mm. This means that 7 speed sprockets can be used for 8 speed cassettes, as long as the 8 speed spacers between sprockets are used.
Sprockets are placed at 4.8 mm spacing, with each sprocket being 1.85 mm thick.
Campagnolo 8 speed cassettes have just slightly different sprocket thickness and spacing, compared to Shimano, so they can be mixed with Shimano 8 speed shifters and derailleurs, with index shifting working good. Provided that appropriate freehub body is used: Campagnolo and Shimano cassettes can’t fit each other’s freehubs – Campy with Campy, Shimano with Shimano.
Note:
As noted in the 2nd post in this bikeforums compatibility thread, “good” depends on your criteria. It won’t be perfect (table 1 lists sprocket spacing and spacer thickness and shows the difference between Campagnolo and Shimano 8-speed cassettes – Campagnolo 8-speed sprockets are spaced as Shimano 7-speed ones, but are slightly narrower, with thicker spacers between them).
9 speeds
Here there is no combining with any other standard. 9 speed cassettes have a unique sprocket thickness and spacing. Campagnolo has their own 9 speed standard, incompatible with Shimano’s.
Sprockets are placed at 4.35 mm spacing, with each sprocket being 1.78 mm thick.
10 speeds
Same sprocket width as 11 speeds, so (more expensive) 11 speed sprockets can be used as replacement, provided 10 speed spacers are used,.
Sprockets are placed at 3.95 mm spacing, with each sprocket being 1.6 mm thick.
This doesn’t go for Campagnolo. Campy 10 speed is only compatible with Campy 10 speed because of different mounting, so an individual Shimano compatible sprocket can’t be mounted.
11 speeds
Sprocket width is the same as for 10 speeds, so 10 speed sprockets can be used, provided that 11 speed spacers are used.
Sprockets are 1.6 mm thick, spaced at 3.74 mm (road), or 3.9 mm (MTB).
For more clarity on this, see below the comment by Nicolas Hanssens and the following four replies by myself and Nicolas Hanssens. I.e, based on my last measurement, and practical experience, Shimano MTB and road 11-speed cassettes have very slight differences that don’t make a noticeable difference when it comes to shifting (video explaining an 11-speed MTB cassette on a road bike pairing).
Campagnolo of course doesn’t accept any 10 speed sprockets. However, just like with 8 speeds, combining complete cassettes is possible: Campagnolo 11 speed cassettes have just slightly different sprocket thickness and spacing, compared to Shimano, so they can be mixed with Shimano 11 speed shifters and derailleurs (and vice versa), with index shifting working good. Provided that appropriate freehub body is used: Campagnolo and Shimano cassettes can’t fit each other’s freehubs – Campy with Campy, Shimano with Shimano.
With 11 speeds there is another exception: it is the only case where Shimano standards for road and MTB differ. For all the other standards, MTB and road cassette is just a marketing term, explaining the number of teeth bigger sprockets have and the difference in sprocket teeth numbers between adjacent sprockets, but with 11 speeds, cassettes really differ. 11 speed road has a longer freehub body, while MTB 11 speed cassette fits 8-9-10 speed freehub. However, sprockets, except the largest one, can be mixed and matched.
Also, SRAM makes XD 11 speed MTB cassettes that fit only SRAM XD freehubs, they can’t be mounted onto other freehub types. These cassettes can accommodate a small sprocket with only 10 teeth.
Update of summer 2018: Shimano introduced new Hyperglide+ cassette standard. These come as 11 and 12 speed cassettes. They require a special freehub body (with different spline design called “Micro Spline“), as well as a special Hyperglide+ chain. The same chain is used for both 11 and 12 speeds, but works only with Hyperglide+ cassettes. Also, derailleurs and shifters of other standards won’t work. Smallest sprocket has 10 teeth.
12 speeds
These come in four different standards.
- First one is SRAM MTB XD. These are compatible with SRAM XD 11 speed freehubs. Smallest sprocket has 10 teeth.
- As of mid-2018, SRAM has introduced NX Eagle groupset, that includes 12 speed cassettes compatible with Shimano (and SRAM) standard freehubs (for 8, 9, or 10 speed cassettes). However, they don’t allow for the smallest sprocket to be smaller than 11 teeth.Sprockets are spaced at 3.65 mm, with the smallest two placed slightly more apart to accommodate for crossed chain when using a crankset with only one chainring.
- Shimano Hyperglide+ 12 speed MTB cassettes, compatible only with Hyperglide+ chains and Hyperglide+ freehubs (using Micro Spline mounting system). Smallest sprocket has 10 teeth.
- In 2018, Campagnolo also jumped on the “more-speeds” bandwagon, introducing their 12 speed groupsets. Campagnolo 12 speed cassettes fit their (Campagnolo) 11 speed freehubs.
One exception: Shimano Dura Ace from year 1984 to 1996 (6 to 8 speeds)
Compatible only with Shimano Dura Ace shifters and RDs from the same period (6, 7 and 8 speeds), because of a different cog pitch.
Correction: cassettes are the same, what differs is the amount of derailleur movement per 1mm of cable pull/release. For a bit more details on this, see my rear shifter article’s section 5.1: “Shimano Dura Ace from 1984 to 1996 (6 to 8 speeds).”
Campagnolo Exa-Drive and Ultra-Drive
Left: Exa-Drive
Right: Ultra-Drive
Stamped circle is just an indicator helping proper alignment when mounting sprockets. No mechanical function whatsoever.
Indented grooves are used to pick the chain up when shifting to a larger sprocket. Exa-Drive indentations are designed to catch the chain pin first, then the outer plate. They work well with 8 and 9 speed Campagnolo chains.
Modern 10 and 11 speed Campagnolo chains don’t have pins protruding out of outer plates, so the newer Ultra-Drive is designed to catch the outer plates directly.
Sprockets of these two standards (with equal number of speeds) can be combined, although it will affect gear changing speed. 🙂
Table of sprocket spacing and thickness:
For a full chart including spacer thickness, total cassette width, freehub mount standards etc, see – bicycle cassette standards post.
| Cassette | Cassette pitch | Sprocket thickness |
| mm. | mm. | |
| All 6-speed | 5 – 5.5 | 1.85 – 2 |
| All 7-speed | 5 | 1.85 |
| Shimano 8-speed | 4.8 | 1.8 |
| Shimano 9-speed | 4.35 | 1.78 |
| Shimano 10-speed | 3.95 | 1.6 |
| Shimano 11-speed road * | 3.74 * | 1.6 |
| Shimano 11-speed mtb * | 3.9 * | 1.6 |
| Campagnolo 8-speed | 5 | 1.9 |
| Campagnolo 9-speed | 4.55 | 1.75 |
| Campagnolo 10-speed | 4.15 | 1.7 |
| Campagnolo 11-speed | 3.85 | 1.6 |
| SRAM 8-speed | 4.8 | 1.8 |
| SRAM 9-speed | 4.35 | 1.8 |
| SRAM 10-speed | 3.95 | 1.6 |
| SRAM 11-speed road | 3.74 | 1.6 |
| SRAM 11-speed mtb | 3.9 | 1.6 |
| SRAM 12-speed mtb | 3.65 | n/a |
| Shimano Dura Ace 6 speeds | 6.07 | n/a |
| Shimano Dura Ace 7 speeds | 5.52 | n/a |
| Shimano Dura Ace 8 speeds | 5.3 | n/a |
* See the explanation in chapter 11.
Last updated:
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thanks for the link
i confirm i have the exa-drive which is the “old” technology.
i would like to change the cassette as i have a 9 sp cassette 13-23 and i would like to have a 13-26 or 13-28 and i was wondering if i could simply buy a new campagnolo 9 sp cassette and mount the latter on my free wheel hub
thanks
For all I know, new Campagnolo 9 speed cassettes are Ultra Drive. They will not fit an Exa-drive hub.
Though vice-versa (Ultra drive freehub with an Exa-drive cassette) can fit, though it offers poor mating interface, possibly damaging (aluminium) freehub splines. But it can fit.
which is the best compatible cassette for SRAM PG-830 11-32T 8speed and SRAM PC830?
please suggest mechanical disc pads for Shimano M415?
For the cassette: any Shimano, or SRAM 8-speed cassette will work.
I go for whichever one I can find at the lowest price, at the moment of purchase.
For the brake pads, Shimano B01S are resing (“organic”) pads that work fine.
If you have brake discs (rotors) that can take sintered (“metallic”) pads, and if you ride long descends with lots of hard braking, then you could look for metallic brake pads.
However, I haven’t tried these brakes with metallic pads, so can’t recommend any particular model.
Hello Relja and many thanks for your website !
I just have one question. You wrote about 11 speed : “Sprockets are 1.6 mm thick, spaced at 3.74 mm (road), or 3.9 mm (MTB).” and “11 speed road has a longer freehub body, while MTB 11 speed cassette fits 8-9-10 speed freehub”.
So I don’t understand why cassette MTB with a larger spaced is narrower that cassette road. Is possible or is a mistake ?
Regards
PS : please be forgiving for my english… 😉
Hello Nicolas,
A good questions. I will edit the article when I find the time, to make that clear. Briefly:
MTB cassettes have a rather large biggest sprocket. So it “climbs” onto the wheel, over the hub’s flange.
Spokes are at an angle, moving away from the hub’s flange, so that makes some extra room.
Road bicycle cassettes have smaller biggest sprocket, so that’s not possible. It would get stuck against the spokes on the hub’s flange.
That is why the freehub body (the part where the cassette is mounted) is wider for 11-speed road bicycle wheels (and cassettes), while MTB 11-speed cassettes fit nicely on the same freehub that fits 8 to 10-speed cassettes.
Hope I’ve explained this well enough. 🙂
Relja
Hello Rejla,
It’s perfectly clear, thank you. The great spider of MTB cassette is like “curved” up the flange of the hub.
But, I was surprised by the difference between pitch of 11s mtb and 11s road of Shimano, so I have mesured today on 3 cassettes :
– Shimano CS 6800 11-28 (road)
– Sunrace 11s 11-28 (road)
– Sunrace 11s 11-42 (MTB)
All the cassettes have the same pitch while Sunrace 11-42 is compatible with Shimano MTB 11s, so I think that Shimano MTB 11s is the same too, no ? Are you sure about the different picth ?
Obviously, it’s better to mesure a shimano MTB to be sure.
Many thanks
Hello Nicolas,
I don’t know about Sunrace. And I will double-check with Shimano cassettes.
This does call for it as well: based on my experiment, it seems that Shimano 11 speed road shifters and derailleurs can work even with a Shimano MTB 11-speed cassette:
Pairing Shimano 11speed MTB cassette with a road groupset
In addition to that, in my experience, Sunrace is generally compatible with Shimano, so I would expect them to have copied the exact dimensions as Shimano makes.
More measuring is in order. 🙂
I have re-measured, with two brand new high/mid-end 11-speed cassettes:
Road CS-R8000 (Shimano 105)
MTB CS-M7000 (Shimano Deore SLX)
The measured width of the entire cassette:
Road: 40 mm (per calculation it should be 39)
MTB: 40.9 mm (per calculation it should be 40.6)
The measured width of the largest 3 sprockets (they are placed on the same spider – but I measured sprocket width alone):
Road: 9.15 mm (per calculation it should be 9.08)
MTB: 9.6 (per calculation it should be 9.4)
Sprocket width:
1.6 for both cassettes
Spacer width:
I’ve measured exactly 2.2 mm for both cassettes!?!
To confirm and eliminate any possible error, or bias, I asked a colleague from Planet-Bike service to do the measuring as well.
He’s mix-matched 11-speed road and MTB cassettes with no problems and was convinced they are exactly the same, suggesting he needn’t even measure.
I agreed they work perfectly fine in practice, but Shimano says they aren’t 1-1 compatible, and I wish to confirm if they really are exactly the same, or just not different enough for it to make a noticeable difference in practice.
His measurement also showed that the MTB cassette is slightly wider.
We hadn’t measured the exact distance between adjacent sprockets, because that is very difficult to measure accurately. At least using the tools we had (callipers). I think it’s more accurate to measure across several sprockets, preferably the entire cassette, as we did.
His practical experience “aligns” with mine: he too has used a Shimano MTB 11-speed cassette, with Shimano 11-speed road shifter and derailleur – and it worked fine.
He also tried what I hadn’t so far: using a Shimano road 11-speed cassette with a Shimano MTB 11-speed shifters and derailleur – and says that too works perfectly fine in practice and on the workstand.
Hi Relja,
Thanks so much for the great work!
You are the new Sheldon Brown, I constantly reference your website for my mixing and matching need.
I had great success using a 2009 campagnolo veloce ultrashift shifters(2.8 mm pull) with a 8 speed (1.4 ratio) campagnolo dérailleur : the resulting movement ( 2.8×1.4=3.92 mm) closely match a 10 speed shimano cassette, even if we know that the pull is not constant.
Hi,
Haven’t tried that combo, but yes, it makes sense – the numbers add up. 🙂
Thanks for the feedback.
Relja
Hi Relja,
Thanks so much for all this valuable information! I’m currently replacing my road bike’s (Giant SCR3) 8-speed components as they’ve worn out and I’ve managed to get my hands on some good 11-speed 105 deals. My bike is relatively old (2006) and the freehub is a Tiagra fh-4400. I believe this can go up to 10-speed (?) but certainly not 11-speed. From your details, would I be able to fit an 11-speed mtb cassette (say an 11-40 SLX cassette – I’d like the range anyway), or do I just have to get a new rear wheel? I probably will change the wheels at some point, but I don’t really have the budget to do it right now.
Many thanks
Hi Leo,
In my experience, a Shimano 11-speed MTB cassette works well enough with Shimano 11 speed road shifter and derailleur.
My friend has been very happy with such setup, for almost two years now. Here’s the video:
Pairing Shimano 11speed MTB cassette with a road groupset
You will most probably need a derailleur hanger extender (like “Wolf-Tooth”).
The video’s description has a(n affiliate) link that shows what I mean.
Relja
Thanks very much for your response, that’s good to know. Do you have any idea about the 11-speed MTB cassette fitting onto my freehub (which is limited to 10-speed road)?
Many thanks
It should fit. An 11-speed road cassette won’t, but an 11-speed MTB cassette will.
11-speed MTB cassettes are designed so that the largest cog is rather large in diameter, and able to “climb” over the hub flange, towards the spokes.
11-speed road cassettes have smaller largest cog, so it would get stuck against the hub flange (and the spokes) on a 8-to-10-speed freeehub, so it requires a wider freehub body.