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Rotor size question (probly for BN)

Apr 3, 2016
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I'm eyeing up an eventual wheel upgrade for my road disc machine, as the stock DT Swiss wheels are a little sluggish. I'm not really interested in carbon wheels as I'm not looking to pay more than £600. I've had a hunt round and seen Zipp 30 course disc wheels for £520.

They are a little heavy, but seem to be favoured in reviews. It looks like they come with adaptors to space them out to 142mm rear, and take 15/12 through axles.

All good so far.

But they only come as 6 bolt, and I have Shimano 785 calipers on my KTM with 140 rotors.

I know very little about disc brakes. Are there 140mm 6 bolt rotors available that would work well with my 785 calipers?

Some people talk about 160mm discs, but surely that would necessitate moving the caliper?
 
Hope do 140mm 6 bolt rotors that would work fine, I'm pretty sure you can get a centre-lock to 6 bolt adaptor too if you really want centre lock rotors (although Shimano do 140mm 6 bolts I think).

Using bigger rotors would mean adding an adaptor to the caliper mount. This is extremely common in mountain biking and they are available for post and IS mounts. 785 is the XT caliper I believe and it's post mount, which means if you wanted to run a 160mm rotor you'd just need one of these:

http://www.chainreactioncycles.com/shimano-mount-adaptor-front-post-to-is/rp-prod13743?gs=1&gclid=Cj0KEQjwj7q6BRDcxfG4pNTQ2NoBEiQAzUpuWwPXzgOAeqJfiFXh6R62tGeSjEgKwUzcJygXjY6geaMaAnB-8P8HAQ&gclsrc=aw.ds

Provided your frame is post-mount (very, very likely, if the caliper bolts straight to it then it is).


Have you considered a hand built set? Hope hubs, decent rims, reasonably high spoke count and you'll have a fantastic set of wheels that will last a very long time.