Why dont brake discs bolt to the hub?

[jason1987]

ive been reading about how to replace them and they dont seem to have nuts? they just sit on the hub, is it because the wheel holds them in place?

[steve_earwig]

There's a couple of small screws to hold the disk in place while the wheel's off but the wheel bolts do a much better job than anything else they could squeeze in there. It's a fairly normal set up.

[jason1987]

oh right, ive been looking online about how to change discs and they dont show any small bolts being taken off, they just remove the caliper and the disc slides off

[steve_earwig]

Just the small screws to undo first. 70 in this here pic:

[mandelbug]

oh right, ive been looking online about how to change discs and they dont show any small bolts being taken off, they just remove the caliper and the disc slides off

The screws aren't always installed when replacing discs. They are only locating screws to save trying to line the wheel and disc up. Makes it fun without the screw I'll tell ya ;)