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Compatibility [02] Cassettes

This post will explain bicycle cassette compatibility i.e. what cassettes can be mixed with which rear shifters/derailleurs. For compatibility with various chains, see: Chain compatibility post. 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 non-friction shifters, i.e. index 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 producers can be interchanged without problems. Shimano’s standard is widely accepted.

Sprockets are placed at 5 mm spacing, with each sprocket being 1.85 mm thick.


7 speeds freewheel

Sprocket width and spacing is the same as for 6 speeds. Here Shimano standard is also accepted and all the producers’ 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.

Left are two Uniglide sprockets (bottom one is the smallest, top one is the 2nd smallest) To the right are two Hyperglide sprockets (bottom smallest, top 2nd smallest)
Left are two Uniglide sprockets (bottom one is the smallest, top one is the 2nd smallest)
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.


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.


Campagnolo Exa-Drive and Ultra-Drive

Campagnolo cassette standards. Left: Exa-Drive Right: Ultra-Drive
Campagnolo cassette standards.
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.

CassetteCassette pitchSprocket thickness
 mm.mm.
All 6-speed5 – 5.51.85 – 2
All 7-speed51.85
Shimano 8-speed4.81.8
Shimano 9-speed4.351.78
Shimano 10-speed3.951.6
Shimano 11-speed road *3.74 *1.6
Shimano 11-speed mtb *3.9 *1.6
Campagnolo 8-speed51.9
Campagnolo 9-speed4.551.75
Campagnolo 10-speed4.151.7
Campagnolo 11-speed3.851.6
SRAM 8-speed4.81.8
SRAM 9-speed4.351.8
SRAM 10-speed3.951.6
SRAM 11-speed road3.741.6
SRAM 11-speed mtb3.91.6
SRAM 12-speed mtb3.65n/a
Shimano Dura Ace 6 speeds6.07n/a
Shimano Dura Ace 7 speeds5.52n/a
Shimano Dura Ace 8 speeds5.3n/a

* See the explanation in chapter 11.

Compatibility posts are also available in eBook (printable and Kindle) and paperback editions on Amazon:

Bicycle drivetrain compatibility book
Bicycle drivetrain compatibility book

51 thoughts on “Compatibility [02] Cassettes”

  1. Hi, do you have any idea if a new veloce 9 speed cassette ultra-drive would work with a 1997-98 campy ergos and rear derailleur?

    Thank you!

    Reply
    • If your ergos are 9 speed and they are compatible with your RD, no reason a 9 speed cassette wouldn’t work.

  2. hi
    can anyone tell me if a Conversion Kit Fixie Bike Single Speed Shimano Adaptor
    will fit or work rather on a Bafang 36V/48V 500W High Speed Brushless Geared DC Fat Tire Rear Wheel Hub Motor cause the hub motor splines seem to look the same as a shimano rear cassette hub at least to me anyway any help would be really appreciated thank you
    oh I did not know how to leave pictures of the things I am asking about but they are both sold on ebay

    Reply
  3. thank you very much for the response I really do appreciate it I hope they will work I will try it anyway so thanks

    Reply
  4. I will let you know what the final result is it will not be until I get the wheel back from the guy lacing the motor he only does regular rims not ebikes but he is doing it as a favor if it is not compatible I actually did find a single speed conversion kit on the luna cycle site that has a cog and spacers so there are options but I will give a detailed followup once I finish the project like I say it will be 1-2 months before I get everything back so but thanks for the inquire and the help I do appreciate it this is all new to me and trial and error

    Reply
  5. Hello Folks,

    i’m planning to upgrade my bike which is 4300D Trek 2009 make. one can find the specs in below link.
    https://archive.trekbikes.com/au/en/2009/trek/4300disc#/au/en/2009/trek/4300disc/details

    i want to change existing rear cassette, shifter, and mechnical disc brakes.
    existing:
    cassette: SRAM PG-830 8 SPEED CASSETTE, 11-32T
    shifter: Shimano EF50, 8 speed
    Brakeset: Shimano M415, mechanical disc w/Shimano EF50 levers
    chain: SRAM PC-830 8 SPEED CHAIN

    am planning to change specs to 
    cassette: SRAM PG-950 9 SPEED CASSETTE ,11-34T
    chain : SRAM PC-951 9 SPEED CHAIN

    Now the question is, which shifter and hydraulic disc brake i have to use ? does the existing derailleur do the job with above mentioned changes? any other things that i need to change/take care for this upgrade?

    Reply
    • My first question when people ask about upgrades is:
      What is lacking with the current setup?
      Do you need lower gearing, higher gearing, or really need an extra gear ratio in between the existing?
      There are 8 speed 11-34 cassettes, a bit cheaper than 9 speed ones usually.

      Factory Alivio RD is very good – if set up properly (like any other).
      For switching to 9 speeds, you’d need to replace the (rear, right hand) shifter, cassette and the chain – nothing else.

      For brakes, Avid mechanical BB5 are good, BB7 even better. That would allow you to keep the brake levers if they aren’t integrated with the 8 speed shifters (i think EF50 are, unfortunately) AND you want to change to 9 speeds as well. EDIT: that is – if sticking with 8 speeds, old levers integrated with shifters would work.

      If going for hydraulic brakes, Shimano Deore are good, while being relatively reasonably priced.

  6. I really don’t need an upgrade. Below are the existing condition:
    1.since existing 8speed cassette and chain has worn out. So, need to replace these.
    2. And I ride this bike in country side during monsoon and winters. So existing mechanical discs were not good at wet conditions.

    Considering above two points I thought of changing it from 8 to 9spd. So what is best ? Please suggest which works out with less $$.

    Reply
  7. I personally prefer lower number of rear sprockets – the system gets more durable/robust. Especially in harsh conditions. So, if it were me, I’d stay with 8 speeds (my “workhorse” bike has 7 speed cassette and friction shifters). My dedicated winter bike (for salty roads to eat away slowly) is 1996 steel 26″ MTB with 6 speed cassette and, again, friction shifters – so no problems if cables get almost frozen – just a stronger tug. 🙂

    If frozen cables are a worry (for winter riding) in harsh winters then, yes, going with Hydraulic brakes makes sense (Shimano Deore are good).

    Our winters are seldom below -10 Celsius and I live in flat lands, so cable rim brakes have worked fine for me. With such winters, on hilly terrain, mechanical discs should be fine. Your bicycle’s brakes aren’t very poor quality, should work decently if properly set up (and with good and properly routed cables and housing).
    Avid BB7 mechanical disc brakes are very good – and that upgrade would be relatively cheap (buying only brake calipers and discs if the current ones are in poor condition), keeping the current brake levers.

    Not sure if I’ve properly explained everything, let me know if you need any more info, or clarification on something.

    Reply
    • @Relja
      While writing this I forgot to mention that even rear shifters has gone bad . So if am changing the shifters as well. What should i consider? I have decided to go with the 8spd + mechanical disc. So which shifters are good enough to my existing set up?

    • For new ones, Shimano makes only Altus class in 8 speeds as far as I know.
      You might be able to dig out an old/left Acera shifter pair, like this one for example.
      Acera are quite good.

      I went friction shifting mode and sticking with it, using a pair of shifters like these ones. But got them for a cheap price. Durable – indestructable 🙂 – and work in all conditions, with any cassette I throw at the back.

  8. @Relja
    Thank you so much for your inputs, now all my doubts are clear. Finally found Acera shifters here with some local dealer. Now am waiting for bb7 callipers. Thanks a lot. ?

    Reply
    • You’re welcome. 🙂
      In my experience, Avid BB7 are probably (among) the best mechanical bicycle disc brakes.

  9. Dear Relja, many thanks for the post. I use a Campagnolo Veloce 9-speed RD (mid-size cage). Combined with DT index shifters also from Campagnolo as well as a Campagnolo 13-26 cassette. I want to change the cassette to a wider range such as 11-34 but the largest cassette Campagnolo is offering for this model is 13-28. If I have understood your article correctly there is not much I can do about it, correct? Or can you think of any wide range cassette that could work (SRAM is the closest to Campagnolo considering pitch and sprocket thickness. Any thoughts? Many thanks, Raphael

    Reply
    • Shimano and SRAM 9 speed cassettes have the same pitch.

      Things to consider:
      Rear derailleur chain wrap capacity and maximum size of rear sprocket it can handle. I explained those terms in the post about rear derailleurs.
      Explanation of how to handle if the chain wrap capacity is not enough is given in the post about chain length for bicycles with derailleurs.
      B screw can be turned in to allow for the RD to accept a bit larger cog that it was designed for. Sometimes, screwing it in the other way round, from the opposite side, does the trick, or using a longer screw. This depends on the RD and RD hanger design. Not always possible.

      Now that’s out of the way, I would say that cassette pitch is close enough. Will it work acceptably well for your use case? Only you can tell (do let me know if you give it a try – might help anyone else with the same dilemma). For example, similar mismatch has worked for this bicycle with 11 speed Shimano drivetrain:

      https://www.youtube.com/watch?v=TCmQZzeH_aU

      In this case, mismatch is just over 0.15 mm, while in your case (9 speed Campagnolo vs 9 speed Shimano/SRAM), the mismatch is about 0.2 mm – could turn out to be just a tad too much. Then again, I expected the same for the 11 speed experiment – but it works perfectly fine after several months now. 🙂

  10. Hey Team!

    Looking for some help, im quite new to the cycling world but im here now and i love it. I got an old bike gifted to me, its a 1993 Specialized Allez sport. I want to upgrade the cassete to have a bigger ring, its an 8 speed 11-25, the thing is a beast. Ive read dozens of pages trying to find out for myself but i just cant sem to grasp it. Does anyone have a recomndation on what size cassste will be compatible? Does any 8 speed work? If you can even send me a link to amazon that would be great or some links to some literature that would do to! Thanks in advance!

    Ty

    Reply
    • For a useful answer, it would take a bit more information. It’s fairly simple.

      Firstly, whether it is a freehub, or a freewheel cassette.
      Also, in case of a freehub cassette, it depends on whether it is a Shimano compatible one, or a Campagnolo. Campagnolo cassettes generally don’t fit Shimano freehubs (and vice-versa).

      Next thing to worry about is the rear derailleur capacity – and max cog size.

      There is a workaround in case derailleur’s chain wrap capacity isn’t sufficient, but in case its largest acceptable cog is too small, a special adapter is needed, or a new derailleur. This depends on how the derailleur is attached to the frame.

      This video shows the adapter in action, while video’s description contains an Amazon link for the adapter:
      https://www.youtube.com/watch?v=TCmQZzeH_aU

      So, there are some caveats and things to consider. I think such stuff is best thought out before spending any money.

      I’ve provided a lot of reading material, without having answered the question. However – think it is better to be cautious, than give any wrong advice. Time spent figuring it all out, in my opinion at least, is a time well spent – making one more knowledgeable, more independent, and able to help themselves.

      Having said that, this is a wild guess without any additional info, but if I were forced to guess, I’d try Sram 12-28 cassette, or, if even more teeth are needed, Shimano Tourney 12-32 – the latter one is more likely to cause problem for the rear derailleur because of the largest cog size.

      In case the wheel uses a freewheel cassette – the above linked cassettes won’t fit it. Also, if it’s a wheel (hub that is) for a Campagnolo cassette, those cassettes won’t fit. Either way – more info and looking into it will be “safer”.

      Hope this helps, at least a bit.

      Relja

  11. I have 9 speed Shimano Alivio trigger + 9 speed Sunrace cassette 11-40T + 10 speed Shimano Deore M610 rear derailleur.
    I tried to get them together but never worked, what should I change cassette, derailleur or shifter?

    Reply
  12. I got Alivio 9 speed derailleur after your comment Relaj, thank you very much for the help.

    Reply
  13. I ride on paved roads, but because of physical limitations, I purchased a MTB. It has a SunRun 7-speed freewheel with 14-16-18-20-22-24-28 sprockets and a Shimano rear derailleur with an indexed shifter. Often, I find myself looking for a taller gear. I have found a 13-15-17-19-21-24-28 SunRace freewheel but I think that I might actually like a 12T sprocket on top.

    What I’d like to do is ADD a 12T and replace the 20 and 22 for a 21T on my SunRun freewheel. That would give me 12-14-16-18-21-24-28. I have searched everywhere and can’t find out about interchange-ability of sprockets. Not only that, but I am having trouble even finding single sprockets for purchase.

    Do you have any information that would help me do this? Or, do you know of a link that lists which sprockets work on which freewheels?

    Thanks!

    -Lawrence

    Reply
    • I don’t know that separate freewheel sprockets are available for sale today.

      There are two solutions that I can think of (one not excluding the other):
      1) Get cranks with larger chainrings.
      2) Change the rear hub (or the entire wheel) for a freehub one, so a 7 speed cassette can be mounted. Cassettes come readily available with the gearing setup you mentioned.
      Note that most modern freehubs will need some extra spacers if mounting a 7 speed cassette on them, as explained in the post about bicycle rear hub compatibility.

  14. Thanks for the quick response.

    I think I’ll just purchase the SunRace 13-28 freewheel. If that isn’t enough, then I’ll look into getting a new wheel with a freehub.

    -L

    Reply
  15. Hi
    a simple question for you the specialists!
    before i buy the wrong part , i would like to be sure if i can put a campagnolo veloce 9v cassette on a campagnolo exa-drive free hub?
    i know that exa drive and ultra drive are the old and new technologies but better asking first before paying!
    Thanks

    Reply
  16. 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

    Reply
    • 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.

  17. which is the best compatible cassette for SRAM PG-830 11-32T 8speed and SRAM PC830?
    please suggest mechanical disc pads for Shimano M415?

    Reply
    • 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.

  18. 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… 😉

    Reply
    • 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.

  19. 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.

    Reply
    • Hi,
      Haven’t tried that combo, but yes, it makes sense – the numbers add up. 🙂
      Thanks for the feedback.

      Relja

  20. 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

    Reply
    • 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.

  21. Pozz Relja; nasao sam jeftino treking biciklo sa manje ostecenja. Treba zamjeniti zadnju felgu i cijeli srednji pogon zajedno sa BB. Oprema je pozadi alivio 8 brzina. Problem je sto sam kupio felgu sa 9 brzinskom kasetom; je li moguće prebaciti kasetu? I drugo pitanje; kad vec mijenjam stavio bih Hollowtech pogon; nasao sam fc 470 za 30e i pise da mu je duljina 121 mm; moj bb cetvrtaljka je 122mm?

    Reply
  22. Hey guys,
    i wonder if I could use any 11 speed cassette on my sunringle SRC hub. Can you help me by telling me a model of such cassette?
    Thanks in advance! Cheers!

    Reply
  23. Hello Relja,

    Thank you for putting up so much information, really appreciate it.
    I had a couple of question that I’d really appreciate if you would answer.
    Firstly, I have a Decathlon Triban RC 100, Flat bar with a 12-28t Microshift cassette and 44t crank, nothing fancy and I ride mostly in the hills. So, is it better to go for say a 11-46t cassette or a small 36t crank for climbing easier? If both, where will I notice the most difference?
    Secindly, I have figured from all the reading that I can go for a 10 speed, 11-46 Deore cassette on my road bike, but I will require a Deore derailleur and a Deore shifter. Is that correct or do I have other options?
    Thanks in advance and stay safe!

    Reply
    • Hi,

      Short answer:
      I’d find some, new or used (2nd hand), friction bar-end shifters, triple road cranks (30-39-50) and a triple road front derailleur, while keeping the RD and the existing cassette.
      For the really low gearing, using friction shifters, one could also use MTB triple cranks with an MTB triple FD (22-32-44 and similar).

      EDIT:
      If the frame has housing stops for the FD (since it’s a 1x as far as I know), or if those can be mounted (depending on the tubing design, that can be more or less of a hassle). If not, then a more expensive, higher quality 1x drivetrain will be needed. Probably costing more than the whole bike when it’s new.

      Other options may end up being less good or at least more expensive for good quality with a wide range.

      Longer answer:

      There are dozens of options – and the choice depends on one’s budget, criteria, priorities etc.
      It boils down to using friction shifters or, if going with indexed shifters, making sure that the derailleur(s), shifters and cassettes/chainrings are all matched to work with each other.
      (friction vs indexed shifters)

      Road RDs can be fitted with a longer hanger to accommodate for larger cassette sprockets – as shown in this video:
      Pairing Shimano 11speed MTB cassette with a road groupset

      If using 10-speed MTB RD (like 10-speed Deore), you’d need a matching shifter.
      For up to 9 speeds, Shimano MTB and road shifters and derailleurs are compatible (older generation 9-speed Deore RDs for example work fine with up to 9-speed road shifters), but the shifter’s number of speeds still needs to match the cassette, of course.

      There are practically dozens of different permutations of those components, with different models and numbers of speeds – and they work fine when they are matched (pull-ratios, number of speeds etc.).
      That’s why I’ve made a series of articles in this compatibility section – so everyone can see what their choice is, depending on what’s available and their other criteria.

      I like cheap and robust – so I choose double or triple chainrings, paired with friction shifters. This gives me a wide range of gearing (low enough for long, steep climbs, as well as high enough for the wind at my back on the flats). 7-speed cassettes (and chains for that matter) are more than enough for me when paired with triple cranks – while friction shifters let me go with practically any RD I get a hold of.

      Unlike triples, 1x systems (only one front chainring) require a huge gearing space to be covered by the cassette alone (1x systems pros and cons).

      So with the Triban 100, you’ll need to decide: changing the cranks, adding a FD and a front shifter, or looking for a greater-range cassette.
      When it comes to the cassette, unless your existing shifter is friction-shifter, you’ll need a new shifter for anything except 7-speed cassettes (if that’s what’s on the bike).

      Another problem is that 10+ speed MTB RDs require MTB shifters (generally speaking) – and those shifters can’t be really elegantly mounted on drop-bars.

      When it comes to which gearing choice is better – this online gear calculator is a great tool, so you can see for yourself.

      I personally find 36T cranks to be a bit too small for the flats – even with 11 teeth at the back.
      For the long and steep climbs, on the other hand, 36T is a lot better than 40 or more, especially with the “normal” cassettes that go to up to 34 teeth (the ones that are not rare, expensive and look like a big plate 🙂 ).

      The only practical way to make 1x drivetrain be versatile enough is to have a cassette with a huge range – which is costly if going with indexed road bike shifters (STI levers) and a matching RD. Cassettes and chains are also more expensive (wide-ranged 10, 11 or 12-speed cassettes).

  24. Concerning 11 speed spacing:
    “Sprockets are 1.6 mm thick, spaced at 3.74 mm (road), or 3.9 mm (MTB). ” Where did this specification come from?

    I’m asking this as I’m converting a bike to 11-speed and considering my cassette options. Given the road freehub is 1.8mm wider, I’m leaning towards a CS-HG700-11 cassette which has the removable 1.8mm spacer to allow install on a 8-9-10 HG Freehub. I may have spoke clearance issues, but the investigation into compatibility has lead me down the rabbit hole of looking closer at Shimano road vs. mountain 11-speed cog pitch.

    If you look up the Shimano parts manual the XT cassette (CS-M8000) https://si.shimano.com/api/publish/storage/pdf/en/ev/CS-M8000/EV-CS-M8000-3854C.pdf and a Durace Cassette (CS-9000) https://si.shimano.com/api/publish/storage/pdf/en/ev/CS-9000/EV-CS-9000-3324B.pdf they both list a 2.18mm thick spacer. I have both of these cassettes and the CS-9000 spacer measures 2.14mm and the CS-M8000 measures 2.24mm. This could be manufacturing tolerance. IDK

    I have these two cassettes and took several pictures side by side. I removed the small cogs to the first 2.18mm spacer and placed them side by side. I did this in a few configurations. See the pictures here. https://photos.app.goo.gl/xkBUNSJuXkFCZMkTA. In two images there appears to be a small stack height difference but I believe that to be due to camera angle. Most of them the sprockets look aligned. In the one that looks misaligned, if 3.74 and 3.9 mm pitch held, the difference across the 8 cogs shown would be 1.28 mm. If you use the cog thickness as reference the difference is much smaller. This with the other pictures lead me to believe they are the same.

    Based on these results I’m lead to believe the pitch between a road and MTB 11 speed cassette is the same. Your real world results (https://www.youtube.com/watch?v=TCmQZzeH_aU) seem to back this up. I have measured several cogs on both cassettes and they are both 1.6 mm thick as you state. This would lead me to conclude they both have a pitch of 3.78 mm.

    I would also point to Shimano’s GRX web page https://bike.shimano.com/en-US/product/component/grx-11-speed.html which list both Road and MTB cassettes as compatible with this group.

    Do you have any explanation of the evidence I have that would still conclude the road and mountain Shimano 11 speed cassette to have a different cog pitch?

    Reply
    • Hi Brain,

      The cassette pitch given is a calculated average after measuring the entire cassette width
      – cassette width, minus one sprocket width (half for each side, to get the distance from middle to middle of the smallest and largest sprocket)
      – divided by the number of sprockets reduced by one (with / (sprocket count – one) )

      My first hand experience and following measurements seem to show that Shimano 11-speed road and MTB cassettes are (virtually) identical (too little difference to make a difference).
      I.e. my last measurement results show 3.84 mm for the road, and 3.93 mm for the MTB cassette.

      If what you say for the GRX is true (no doubt – just at this moment the page says “maintenance”), that means Shimano implies they are identical for all practical purposes.

      I’ll edit the article with a note that whatever the exact measures and pitch are (not sure how to measure it accurately in a more “direct” way), the cassettes can be mix-matched for all practical purposes.

  25. Thanks for the info. I’ve seen the 3.74 and 3.9 floating around the internet. Perhaps they got it from you :). I’ll have some more accurate measurement tools available to me later this year so I’ll see if I can come up with anything better. I feel like short of 3D blue light scanning and 3D modeling, we will never know.

    I’m also curious if maybe it’s not 100% even. IDK. It’s hard to measure across the carriers. I’ve come up with 3.8 – 3.85 as well. I don’t think my calipers are that accurate so I’ll take it with a grain of salt. I’ll have some larger micrometers available soon so I’ll measure again.

    I’ve noticed the cogs on the carrier of my XT cassette are thicker than the Dura Ace cogs. Especially the 40t. The Dura Ace cogs seem more consistent. This makes comparing the two hard. That’s why in the pictures I compared the smaller cogs and they seem more consistent.

    This is becoming academic. I agree that for all practical purposes they are interchangeable.

    I can say for sure that my CS-M8000 11-40 11sp XT cassette on my 8 speed Dura Ace wheel (130mm spacing) works in the smallest cog without hitting the frame of my 2000 Cannondale XR800 and clears the spokes in the 40 by a large margin. This seems to give me an upgrade path to 11 speed with an CS-HG700-11 Cassette and 11-speed shifters and GS rear derailleur. It uses a removable 1.8 mm spacer for MTB HG compatibility (or older road 8,9 hubs). Good food for thought for anyone looking to upgrade an older bike. This bike has 1996 Dura Ace which leaves few options to replace worn parts. I was glad to see your video and comments on your mismatch of road and mountain with no issues after one year. This gave me confidence to move forward.

    I’m glad I found you. Thank you Google.

    Reply
    • I got some more precise (digital) callipers, but I don’t do any re-measuring, until I see something being off – as was/is the case with the 11-speed cassette compatibility.

      The whole compatibility series of articles was written for my own convenience – with a constant shortage of parts and money in my country and always mix-matching. The main reason for translating it into English was to more easily answer frequently asked questions and for “why not” reasons. 🙂

      However, judging by the number of comments, it seems that a lot of people are having the same dilemmas and problems, so it ended up being a lot more useful than expected.

      It’s understandable that bike companies have both financial and legal reasons to keep their “official” recommendations a lot more “conservative,” but it does make one’s life a lot more difficult when mix-matching, instead of buying a whole new groupset.

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