Shimano say that their lower end hydraulic brakes (e.g., BR-M365) are compatible with 'wide' rotors. See http://productinfo.shimano.com/#/com/2.0?acid=C-461&cid=C-460 for details.

Wide rotors are those numbered below 60, e.g., RT54. Narrow are those higher than 60, e.g., RT66.

wide/narrow rotor

The wide rotors (i.e. those below RT60) are made of low-quality metal and claim to be incompatible with metal pads.

What are some third-party, etc. options for getting better quality rotors?

  • I am looking for 3rd party rotors as well for wide shimano calipers (in the search for a rotor that reduces wet squealing). Did you ever find out a third party that indicates if their rotor is compatible with wide/narrow Shimano calipers? May 16, 2023 at 12:25

1 Answer 1


As you mention SM-RT54 and 66 rotors, I will infer you have Deore level calipers. (Deore is not 'low end' IMHO, as the 'cheap A's' (Alivio, Acera and Altus) and almost unmentionable Tourney are below it.)

If you check out the Shimano Product Line docs for Deore you will see that the SM-RT64, SM-RT54, SM-RT66 and SM-RT56 rotors are all compatible with the BR-M6000 and BR-MT500 calipers. The SM-RT64 and SM-RT66 are both metal pad compatible.

Note that the BR-MT500 caliper is not metal pad compatible though, so you should check your caliper compatibility.

  • 1
    There aren't any Tourney hydraulic brakes. I am, to be clear, referring to low-end brakes, specifically those beginning BR-M4, BR-M3 and possibly BR-M2, e.g., BR-M365. These are Altus/Alivio/Acera level. The compatibility document productinfo.shimano.com/download/?path=pdfs/archive/… says at c-460 "Narrow type 2 piece rotor are not compatible to caliper for Wide type rotor because of interference." At the table it says BR-M3xx and BR-M4xx et al are 'Wide' type, and it lists only the SM-RT54/56/30/26/10 as compatible.
    – thelawnet
    Mar 6, 2018 at 19:11
  • also "Do not use these combinations for a reason of interference between brake caliper and adapter of rotor."
    – thelawnet
    Mar 6, 2018 at 19:17
  • OK, I was wondering where the narrow/wide thing came from. (It's always a good idea to link to any docs you are referring to in your question.) Note that it's not just the rotor that is not metal pad compatible, the calipers are not either. Basically it seems Alivio and below are not meant to be used with metal pads. Mar 6, 2018 at 19:25
  • I don't see any reason why the caliper itself would be incompatible with resin pads, apparently the issue is with the lack of heat treatment on the rotors. Hence the desire to use better rotors.
    – thelawnet
    Mar 6, 2018 at 19:41
  • Insufficient heat dissipation and torque capacity. If you go here and click on the BR-MT400 link the spec sheet clearly says there is only a resin pad option Mar 6, 2018 at 19:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.