Shimano SM-RT900 Dura Ace Center Lock Rotor on Ultegra Is it possible to fit the Dura Ace Rotor (SM-RT900) if you have the Ultegra R8020 hydro disc .

 

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Yes, you can use SM-RT900 rotor with with a BR-R8070 caliper. Calipers rarely have rotor incompatibility (width, size) and almost never across the same manufacturer product range. There are some things to keep in mind, but none of potential issues are caused by particular caliper/rotor combo:


SM-RT900 has Centerlock interface. The front hub must be either Centerlock-compatible or you can get a Centerlock to 6 bolt adapter.
Rotor size. If you plan to replace an existing brake rotor and decide to go with a different size (140mm or 160mm) and assuming your setup uses a regular flat mount fork/caliper, then you'll need to flip the caliper mounting bracket between 140 and 160 rotor size positions. Hopefully you don't have a rare fork that dictates only a single caliper position.