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The ceramic pistons on my brand new BR7070 brakes won't depress at all even with quite a lot of force. There is also a subtle grinding noise when trying to depress the pistons. Did I somehow crack the brand new pistons? How much force does it take to depress these?

  • Hi, welcome to bicycles! It's not clear to me what the question is. Are you asking for diagnotic tips? Maintenance instructions? If anyone else has had a similar problem? Please edit the question to be more clear about what you're asking. – DavidW Apr 26 at 21:15
  • If its a brand new caliper, look into warranty before you go too far. – Criggie Apr 27 at 21:19
  • I’m voting to close this question because it has been answered successfully. – Criggie May 10 at 10:18
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I disassembled the caliper and the ceramic pistons were both shattered. They were either shattered on arrival or this was from trying to put a bleed block in when the pistons were slightly out. This pushed the pistons into a slight angle. Then they shattered when squeezing the brakes.

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