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Axle size

Started by Ddaybc, April 04, 2022, 10:54:38 AM

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My rear hub drive has an 18 mm axle nut. What is the size of the actual axle? Is the replacement nut an M9 or an M12 as my axle looks like it's about 13 mm across (measured with a tape and while the nut was still on the axle unfortunately.)?

I need to find out as I am going to purchase a Pinhead security system for the quick release for the front axle, the rear solid axle nuts as well as for the seat posts etc. I don't want to order the wrong things.



If anyone is interested I have been told by PinHead that an 18mm nut is called an M12. Apparently the M designation is for the thread diameter and not the nut size. I wasn't sure so here it is. An M6 bolt is 6 mm across the threads, a M8 is 8 mm etc.