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Item # AVI000D

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  • Black, 20mm post mount ($20.00)
  • Black, 10mm post mount ($20.00)
  • Black, 40mm post mount ($20.00)
  • Black, 30mm post mount ($20.00)
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Item # AVI000D


Avid's 10, 20, 30, and 40mm Brake Adapters include bolts and spacers to fit a variety of Post Mount configurations. To find the correct components, pick a rotor size and fork/frame interface then reference either Sram's caliper mounting and spacer configurations doc or the tech specs to the side.

  • All necessary bolts and spacers included

Tech Specs

[10mm] 10S fits 170mm Front Rotors, [20mm] 20S/20P fits 180mm Front and 160mm Rear Rotors, [30mm] 30P fits 200mm Front and 180mm Rear Rotors, [40mm] 40P fits 170mm Rear Rotors
Attachment Type:
140mm rear post mount, 160mm front post mount
Manufacturer Warranty:
2 years

Reviews & Community

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Avid Post Mount Brake Adapter

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Here's what others have to say...

5 5


  • Familiarity: I've put it through the wringer

I picked up the 20mm post kit, mainly because I needed longer hardware for a Shimano post mount that I had laying around. I'm always happy to have a handful of spare washers and spacers though!

3 5

Buy a set for each wheel

  • Familiarity: I've put it through the wringer

The kit gives you a "standard" and "CPS" set of spacers. Throw away the spacers you don't need. You will need to buy two sets if you have two identical brakes.

5 5

Nothing fancy, but they work great!

  • Familiarity: I've put it through the wringer

Few things are standard anymore and that goes for frame and fork specs or rotor sizes across the various disc brake options that are available. Use these kits to adapt your rotor size to your frame's specs.

These kits work great and include two sets of hardware so that you'll be set whether or not your brake calipers require CPS washers (many Avid's do). I ordered a couple of kits so that I could run a 160 mm rear rotor on a 140 mm post mount frame and also a 180 mm front rotor on a 160 post mount fork. The included instructions confirmed the correct location of all of the required washers and spacers so that I didn't have to guess.

Unanswered Question

My 2012 Specialized Stumpjumper HT is 140mm...

My 2012 Specialized Stumpjumper HT is 140mm post-mount rear with the 20mm spacers on it to work with the 160mm rotor/Avid Elixir 7s that came stock on the bike. I'm swapping the brakes out for Shimano XTs with 160mm rotors. Can I just continue to use the Avid spacers that are already on the post mounts? Do I need to get the Shimano-specific post-mount adapter?