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Item # SHI0108
Item # SHI0108Like much of life, making your Shimano disc brakes work with your 160mm rotor is easy --once you learn how to figure out which adapter you need. Whatever you have, we can either sell you the adapters to make it work, or tell you that what you have is enough.
You need to know three things -- what kind of mount your Shimano disc caliper is, International Standard (ISO) or post mount. If it goes on the front, you need to know what your fork is: ISO, post-mount, or a few special cases (Marzocchi 20mm axle, Boxxer-type). And, you need to know the rotor size that you're trying to fit -- in this case, it's 160mm. If you're trying to diagnose what you already have and/or what you need, here's how to do it. The Shimano adapters all have a model number that starts with SM. The Mount Adapter acronym is MA. Front brake is F. Rear brake is R. Rotor Size is 160, 180, or 203. Caliper Mount Type will be S for ISO/International A, and P will represent Post. And the last letter will be for the frame or fork mount type: S for ISO/A, P for Post, B for Boxxer, Z for Marzocchi 20mm Axle as well as QR20Plus and DH ISO. Thus an adapter that reads SM-MA-F-203S/P is Shimano Small Parts Mount Adapter Front 203mm Rotor with ISO caliper on a Post type fork.- Durable alloy construction
- Mounting hardware included
- Compatible with ISO and post-mount calipers and frames/forks
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Reviews & Community
REVIEWS
Tim J203mm brakes on RM Instinct
I loved my X2's with 180mm rotors, but I wanted more braking power without spending $500+ dollars for 4-piston brakes. So I did what a lot of people do in my situation and bought big ol' rotors and some adapters. For $100, I picked up rotors and adapters and I now have a noticeable increase in power while keeping the brake set I love.
As others have said, the part numbers are very confusing, so hopefully these photos will clarify what's needed for 160mm and 180mm post mount applications.
Sidenote: I was advised to avoid the Hope 203mm two-piece rotors on the Fox 34 due to clearance issues. I'm glad I chose the one-piece. It's a very tight fit but they clear, and they're about $15 less. Stoked!
Tim JShimano brake adapter 180 to 203
Part # SM-MA-F203 (180mm to 203mm), Post/Post Front/Rear
Hope X2 brakes with 203mm Hope one-piece rotors onto my Rocky Mountain Instinct (180mm post mount).
Tim JShimano brake disc adapter 160 to 203
Part # SM-MA-F203 (160mm to 203mm), Post/Post Front/Rear
Mounted Hope X2 brakes with Hope one-piece 203 rotors on my Fox 34 (160mm post mount ) fork. I recommend one-piece rotors on the Fox 34 to avoid clearance issues. It's a tight fit.
Alex looking for front fork Post mount to Flat claiper, 160mm Center lock disc adaptor, for 2015 Cannondale 12
Jordan PorterPerfect.
- Familiarity: I've used it several times
Got some to make my ripmo 203 F/R. Some pictures don't actually match what you're getting.
Katie HarkerGearheadWorks with SRAM Guides
- Familiarity: I've put it through the wringer
Used this for a hardtail build. The profile worked well with the shape of the SRAM Guide RSC calipers.
taylorEmployeeAs Expected
- Familiarity: I've put it through the wringer
Does its thing and does it well. No complaints for this here.
David M.What is the purpose of the little plastic clips that come with the mounting hardware?
David M.Since asking this question I found the answer in a Shimano service manual. For anyone curious, the little plastic clips are supposed to be attached to the bolts after they are tightened to prevent them from loosening over time. The bolts come with thread lock already applied so the clips don't really seem necessary, and that explains why everyone gets by just fine not knowing what they are for.
Robert JensenGearheadPart works great, Part #'s not so much
- Familiarity: I've put it through the wringer
If you need it you need it. Simple adapter to hook it up.
Hit us up if you have any questions on the application for your bike.
Ben BrownEmployeeFor forks with 180mm mounts
My fork has 160mm mounts so this one doesn't work for using a 203mm rotor.
Andrew MeehanEmployeeA must.
Shimano's part numbers can be confusing. Be sure to hit the "Chat Now" button to get help from a Gearhead who can help confirm the correct adapter for your frame.
Shaegood luck!!
- Familiarity: I've used it several times
work great if you can figure out shimanos part numbers and fitment!!!....wooo hoooo!
Sunn KimEmployeeNecessary
- Familiarity: I've put it through the wringer
Great little adapters to ensure that your brakes fit your bike.
TomJEmployeeRequired parts
- Familiarity: I've put it through the wringer
If you want to follow the trend of having a 180mm rotor for the rear brake, you will need this if you have a Santa Cruz or any other brand that uses an international standard brake mount.
Taylor BentzEmployeeDoes its job
- Familiarity: I've used it once or twice and have initial impressions
Does what you need it to do!
Kevin KEmployee
Avg. ride time: 3h 11m per week- Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.
Necessary
- Familiarity: I've put it through the wringer
Works well with not only Shimano, but other brands as well. Just be sure to get the correct one for your application and should be smooth sailing.
Ben B.EmployeeDoes what it should
Easy to use and does exactly what it needs to do.
Craig LGearheadWorks as intended
- Familiarity: I've put it through the wringer
You will likely need one or two of these to mount up your disc brakes, get the right ones for your set up and youre good to go!
Fritz HanselerMount it up
- Familiarity: I've put it through the wringer
Durable and easy to install, brake adapters are necessary on many frames and forks if you are running a larger rotor size.
Vinny MauroEmployeeWorks with Avids Too
- Familiarity: I've put it through the wringer
These work for any brakes as far as I know, I used them to mount my Guide brakes with some 203 rotors. So if you have trouble finding certain adapters for certain brands in stock ever, know that you can cross brands since the spacing is all standardized. Full disclosure, can't guarantee it works with all brands/caliper shapes. But I have used shimano adapters with several sets of Guide brakes over the last few years so I can say that works for sure.