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Brake adaptors for 203mm rotors

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Recently I installed new shimano hydraulic brakes from passionate, I I'd like to upgrade rotors. What kind of adaptors do I need for 203mm rotors? I'm also going to buy suspension fork from lunacycle, would I need different adaptor for it? P.S. I have sondors X 7 speed.

Edited by Medicus

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Hey @Medicus

If you bought Shimano Hydraulic Disc brakes from Pasion  

Here is what I bought and installed and should be perfect for your Sondors X. But I use a 203mm front (several times the braking power as the rear) and 180mm rear which is the conventional setup for an EBike that weighs as much as mine loaded with cargo (Heavy).  


If you'd prefer a 203mm rear these adapter are available from the same store. https://tinyurl.com/Reddys-Adapters

These are the discs I installed : 


I have this setup on two bikes. Easy Peasy...No Fuss.






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The Luna Lander uses Post mounts not IS mounts like your current fork on the X, so the adapter you need for the front is completely different. 

I have found that despite the supposed universal nature of brake mount adapters, you wind up shimming them a lot more, or even having to step down a size if the correction you need is in the opposite direction - if you buy one brand of  brakes and another brand of brake adapters.  There can be lots of reasons for this. 

Lets say you buy Avid BB7 brakes - a common upgrade - and you even buy Avid adapters... Avid brakes assume you also use their adjustable-position semi-hemispheric washer kits in between the brake and adapter.  So if you try a direct mount like you would pretty much any other brake... they'll come up short and you'll be scratching your head and adding flat washers and longer bolts to make them fit (I lived this dream on a different bike and bought a few sets of washer/mount kits on Fleabay to solve the problem).

Before I point out specific adapters... why don't you just go 203mm front and 203mm rear?  There's no reason not to.  Other Sondors owners have done it with your Shimano e-brakes and it works just fine.  You will only have to buy one kind of spare rotor to fit both axles and most important of all... it looks cool.

So, with a fixed Sondors fork and Shimano hydros, whats the adapter?

This is the Shimano adapter for the front on your Sondors fork with IS mounts.


This is just the first place I got when I googled for a result.  I bet you can find them on Fleabay but probably not much cheaper.  And I have bought brake adapters from these guys before so they at least appear to be a real company.  W

When you add a Luna Lander in front, you will need a post-to-post mount:


See the difference because of the mounting type?  Its huge!

Now, your rears.  I am going to just go ahead and recommend an IS 203mm.  and its not the same as an IS 203mm front adapter as you'll see:


Again... both are 203mm but look at the difference in the front vs. the rear post adapters.

You can make all sorts of other sizes work.  These stand the best chance of doing the job with none of the monkeying around that brake whisperers ordinarily expect as part of the game.  But if monkeying around is needed, keep some standard M6 washers handy in case you do need to shim things out a tad.  You could wind up putting them in a variety of places as all of the mounting bolts are M6.  Be advised though if you are shimming the adapter at the IS mount (the bottom) then you are reducing the surface area contact that the brake mount would have had if you didn't shim it at all.  Generally its better to shim at the caliper on top of the mount.  And if you DO have to extend it outwards, get longer bolts so you keep lots of thread engagement.

Also, get some M6 serrated ring washers to put between the flat washers you will use and the socket caps that hold things together.  They take up almost no thread space and work splendidly to lock bolts in.  Lastly, if you must use thread locker, use Vibra Tite NOT Loctite.  The former never hardens and just is a restrictive goop that does what you need and no more: Lets the bolt resist vibrations and loosening without locking it in so you will strip it next time you revisit the thing.

Good luck!

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