You need 3-5 70mm m14 bolts to hold the old rotor to the hub.

Pipe flange should hold the force but you would have to drill it out for 1" bolt to fit through as pipe thread is not the same as a bolt. You can use a 7/8" bolt and 1" flange.

The beauty is: you don't have to just use the bolt + turn: once you snug it good and tight, hit the bolt with a hammer.

Tighten, hit, repeat as necessary.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)