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Ahem... the next issue in this fascinating journey 🙂
I have acquired a set of Guide RE brakes with 203mm rotors to furnish the Big Al build. Checking the pre-built bikes, they come with 180mm rotors, so I assumed I would need a 180-203mm adapter to fit the callipers.
I purchased a couple of Shimano adapters (SM-MA-F203P/PMA) and attached the first on the rear, but the rotor seems way too large still (see the photos - the callipers need to be unscrewed nearly all the way to fit the wheel on).
Where have a I made a boo boo this time? Are Ragley frames made for much smaller rotors, so I should have bought a different adapter?
Secondary question: The adapter came with a set of washers (pictured). When would different ones be used where?
Thank you!
Whilst the builds may come with 180mm rotors, the standard mounts may be for 160mm rotors and therefore require adapters. If you check the frame only listing it should state what the standard size post mount is.
Do you have a 180mm rotor for comparison?
Edit. Just checked a couple of sites and it's a 160mm mount.
https://www.ragleybikes.com/products/big-al-hardtail-frame-2022
Every day's a school day... thank you!
Your picture of the rear brake shows you've installed a front brake adaptor the wrong way round so that's probably got something to do with it.
Yeah if you look up a full built big al it has an adapter on it for the 180mm rotors - so the frame must be 160mm pm
Wrong way round??
There's no indication with these adapters that there is any difference between front and back - indeed, I've just ordered a 160-203mm adapter from Uberbike - they don't appear to be any different front/back either.
Shimano's manuals that they supply with kit are rubbish - it's just a multi-language one-pager saying that you should scan the bar code to get to the manual. When you follow the bar code link it just takes you to a 1-page PDF naming the part, but without any form of installation guide/instructions.
Advice much appreciated all 🙂
Wrong way round??
There’s no indication with these adapters that there is any difference between front and back – indeed, I’ve just ordered a 160-203mm adapter from Uberbike – they don’t appear to be any different front/back either.
The adaptor isn't the same at both ends - the thicker end should be at the front otherwise it doesn't place the calliper in the correct position. Theres an arrow on them that points forward/up if front
but you need a diffent adaptor in any case
The F on the adaptor box/model number relates to front and the arrow needs to point upwards (towards the bars or towards the saddle)
Good knowledge skills - thank you 🙂