Already available for SRAM Eagle’s 12-speed rear derailleurs, now you can upgrade you new Shimano M8100 XT and M9100 XTR 12-speed rear derailleurs, too. The new Ceramicspeed OSPW X for Shimano uses a carbon fiber-reinforced cage with oversized aluminum pulley wheels and, of course, ceramic bearings.

You’ll have two bearing options, their standard ones for $549, or their even smoother coated ceramic bearings for $649. Both use a 14-tooth upper pulley and an 18-tooth lower. Full compatibility includes Shimano XTR M9100-SGS, Shimano XTR M9100-GS and Shimano XT M8100-SGS, and cassette compatibility from 10-51 teeth.

It’s adjustable with two different spring tension settings (the SRAM Eagle model has three). Normally, larger pulley wheels would mean you’ll need to lengthen the chain, but Ceramicspeed has moved the pulleys slightly closer with a shorter cage to keep chain length requirements about the same. Pulleys are available in black or gold anodization.

They haven’t published numbers for this set specifically, but their lab testing claimed a 40% drag reduction for the Eagle unit, so we suspect similar numbers here.

12-speed ceramic bearing pulley wheels for shimano M8100 XT and M9100 XTR rear derailleurs

Too much? Don’t want to completely void your derailleur warranty? Just swap in the new 12-speed Shimano pulleys for the stock units inside the stock cage. They’re both 14 tooth, and both use a narrow-wide tooth pattern. Retail is $349 for standard, and $429 for coated.

All items come with a small dropper of Ceramicspeed’s bearing oil, and they have maintenance videos on their site to help you keep them performing at peak level. So, you know, until their complete mountain bike drivetrain group is ready, these hop up kits can bring your drag (and checking account) closer to zero.


  1. Crash Bandicoot on

    $650 to make your bike shift worse. This company is a prime example of why bike industry “engineering” is a humungous joke.

    • K-Pop is dangerous to your health on

      Not sure how productive making broad sweeping generalizations about engineering is. One or a handful of brands that push this kind of nonsense don’t dictate any kind of norm. There are snake oil salesmen in every industry. That being said I’ve seen the sales activity for this company’s products though a large retailer I worked for and they sell out of everything. For as ridiculous as this stuff is there are plenty of people out there with deep pockets that are eating it up.

    • Fred Gravelly on

      Agree although I think br is also to blame for shamelessly making free advertisements for these kind of companies day in/day out.
      My solution?: question these companies about their products if they seem fishy, make them explain their data more in depth & call them out or dont publish them if they are selling $600+ ceramic wolf tickets!!

  2. Frank on

    Serious question: how many people buy these things? Has anyone ever seen Then IRL? They are so ridiculously expensive and offer so little real-world benefit, I really just can’t imagine who would buy one.

  3. Velo Kitty on

    > $649 for coated ceramic bearing pulleys? Really?

    Well if I use my $600 unemployment check towards it, I’ll just need to round up forty nine more dollars to purchase it.


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