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Discussion Starter · #1 ·
Yes why is there adapters for center lock rims so they can use 6 bolt rotors but not he other way around?
i for one can´t use XTR ice tech rotors on my roval rims only XT 6 bolt ice tech rotors so when i move from magura to XTR M987 brakes and use XT ice tech rotors i gain some weight on the bike which is petty but i believe i can cope with it.
 

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For the same reason that you can't get an adapter for a QR hub that lets you use a 20mm axle... you can add something to the smaller size to fit the larger (e.g. an adapter for 20mm hubs to run QR) but you can't fit a smaller diameter centre-lock rotor on a six-bolt hub because the attachment area is already too wide for the centre-lock (not sure that explains it clearly...?).

You'd have to put it next to the 6-bolt mounting and that would throw the rotor way off line with regards to the calipers (unless you can get specially custom rotors that have the braking surface off-set to the plane of the mounting?).

It would also be a bit like trying to fit a 150mm rear hub in a bike with 135mm dropouts.

Or a quart in a pint pot. You get the idea...
 

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Centrelock was designed to be able to accommodate 6 bolt rotors with a simple adapter. That means that its splined interface must be smaller than the 6 bolt pattern. It was also designed to use Hyperglide lockrings, which have about that same size.

There is no room to stack a splined boss on top of the 6 bolt flange on 6 bolt hubs. That arrangement would be too thick and it would run into the fork leg or frame. If Shimano had made the Centerlock splined boss very large in diameter such that it was bigger than the 6 bolt flange, then you could have an adapter that you are imagining. But that design would be ridiculous, so they didn't do that.


All in all, I'm completely in favour of centre lock, but there are good reasons for 6 bolt too, like lower cost (not even including the license fee for Centerlock). Centrelock is much easier to work on, however, and I believe it is safer.
 

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Yes why is there adapters for center lock rims so they can use 6 bolt rotors but not he other way around?
i for one can´t use XTR ice tech rotors on my roval rims only XT 6 bolt ice tech rotors so when i move from magura to XTR M987 brakes and use XT ice tech rotors i gain some weight on the bike which is petty but i believe i can cope with it.
I have never been able to mount any disc brake rotor to any rim. The rotor fits to the hub. The hub is connected to the rim with spokes and the complete structure is a wheel.
 

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Discussion Starter · #6 ·
heheh ok my misstake
so i have understood i can not use a centerlock rotor on Rovla Wheel/hubs
i have heard i can fit the 29" wheels from Shimano but i read they can´t fit the 142 axle that is on my Epic the rear wheel as they only have the 135mm quick release?
 
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