1 1/4 inch wrench if I'm guessing correctly.

Originally Posted by
JonE
The threads for that bolt are opposite turning to get off. I think it is a 34mm thin open ended wrench required, I got mine from a bicycle supply house, about 5 or 6 dollars. Put the wrench on the nut and wack with a hammer (righty loosey, this time) and it should come right off. Some have had trouble getting it off, though.
Good luck
95 E34 530I V2.37
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