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Hi All,

I have a Canyon Ultimate CF SLX Disc and I'm in the process of upgrading to Ultegra R8000 (anyone want to buy Ultegra 6800 crankset as well as front and rear mech?! - once my new shifters arrive anyway).

Shimano recommends 140mm rotors, as mentioned in road.cc's review http://road.cc/content/review/217032-canyon-aeroad-cf-slx-disc-80-di2

Why do I want to switch to smaller, less powerful rotors? It's quite simple, my Canyon is essentially my dream bike, so the aesthetics are very important and I think 140mm rotors look much better.

I weigh 67kg and I don't do mountain descents, so I highly doubt heat build up or brake fade is going to be an issue. I also don't ride my Canyon in poor conditions (mud/rain), so I'm not overly concerned about braking power.

I'm new to flat mount disc brakes... I assume it is as simple as  (changing the rotors - obviously) removing the rear 160mm spacer and flipping the front spacer to the 140 position?

Just want to make sure I'm not missing something (like frame compatibility).

Cheers!

 

10 comments

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shutuplegz [53 posts] 3 months ago
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I've done the same as you a couple of times in the past for the same reasons as you without any problems, on cable and hydraulic disc brake setups. Plenty of fade-free braking power for me (60kg) even on big long descents, with good cable discs (TRP Spyre/Spyre SLC).

On the 2017 Canyon ranges they seemed to supply the smaller frame sizes (s and xs) with the smaller rotors anyway which was a tick in the box for me but on the 2018 ranges they don't seem to mention this. Might be worth a go on their 'live chat' system?

From my experience frames and forks generally seem to be designed for either, with just a change to the spacers required. As you say, with flat mount it is even easier as you just swap the fork adaptor around (usually) and remove the rear brake spacers.

The only issue I have encountered is that due to the closer proximity of the calliper to the hub, on my cable disc bike the slightly bulkier TRP Spyre cable calliper did end up very close to the spokes but not so much that it contacts. I did have to be careful with calliper lateral adjustment and pad adjustment though as it would have been possible to adjust it such that the calliper skimmed the spokes. With flat mount hydraulics you will be fine though.

The other thing to consider is that you will need a bit more brake hose pulled through and I am always careful to ensure that none of my cables/hoses rub, which might need some attention once you have moved the calliper towards the hub.

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CXR94Di2 [1906 posts] 3 months ago
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If you're light weight then 140mm should be ok. On the other hand I'm 95kg and are pleased mine are 160mm with sintered pads

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wellsprop [631 posts] 3 months ago
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Cheers guys.

I've just read in a few places that the Canyon Ultimate is designed to take 140's anyway, so there won't be a problem with fitting.

Canyon built up my bike with enough slack in the hoses to go the extra 10mm required to switch to 140's.

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StraelGuy [1110 posts] 3 months ago
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Get the 140's. I just converted 5800 to 685 hydraulics and was worried it'd need 160's - it SERIOUSLY doesn't. Hydraulic 140's stamp ALL over rim brakes for power. After I tried mine, the story of a chap on here who crashed badly because he was on a European style bike and accidentally grabbed the rear brake on a sharp, wet descent suddenly makes perfect sense - he wouldn't have stood a chance.

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BarryBianchi [419 posts] 3 months ago
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140s on a road bike are more than plenty, especially full hydro.  Mine will stop me flat out down a hill in the wet with two finger moderate pressure.  Anymore and you'll just be gettng into an ucontrollable skid much quicker.  It's by far and a way tyre grip that's the limiting factor, not brake power.

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velochris [22 posts] 3 months ago
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You should be fine given your weight and riding style. If you were heavier and a poor descender in the mountains it may be an issue.

This is with the "official" caveat of using Shimano Ice tec rotors and finned pads. Shimano claim this combination reduces rotor temperature. This is why a smaller rotor (ie area to heat up) can be accomdated. I do not know if other riders can provide anecdotal evidence that non ice tec combinations are fine with 140mm. Guessing general non mountain riding will still be fine.

If the 6800 chainset you are selling is 170mm and 50/34 then pm me.

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wellsprop [631 posts] 3 months ago
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velochris wrote:

You should be fine given your weight and riding style. If you were heavier and a poor descender in the mountains it may be an issue. This is with the "official" caveat of using Shimano Ice tec rotors and finned pads. Shimano claim this combination reduces rotor temperature. This is why a smaller rotor (ie area to heat up) can be accomdated. I do not know if other riders can provide anecdotal evidence that non ice tec combinations are fine with 140mm. Guessing general non mountain riding will still be fine. If the 6800 chainset you are selling is 170mm and 50/34 then pm me.

Yeah, I need to buy the new rotors anyway.

The cranks are 172.5 52/36 I'm afraid! Annoyingly, I've found out that I need to wait until late November before my new groupset parts arrive anyway  2

 

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StraelGuy [1110 posts] 3 months ago
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Take a look at these, a third the price of most brand name discs and the quality is absolutely TOP notch. I found them looking for round discs as I don't like the aesthetic of wavy ones...

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BarryBianchi [419 posts] 3 months ago
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StraelGuy wrote:

Take a look at these, a third the price of most brand name discs and the quality is absolutely TOP notch. I found them looking for round discs as I don't like the aesthetic of wavy ones...

bookmarked.

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wellsprop [631 posts] 3 months ago
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StraelGuy wrote:

Take a look at these, a third the price of most brand name discs and the quality is absolutely TOP notch. I found them looking for round discs as I don't like the aesthetic of wavy ones...

That's a pretty good price! I'm using centrelocks now though.