Rear axle washer 2018 softail

[Slider1950]

Tonight I noticed that the rear axle washer that goes under the rear axle nut has a flat side and the other side has a rounded outside edge and slightly larger diameter. I had the rear tire replaced a few weeks ago and the dealer installed the washer with the flat side inward against the rear frame. The side of the washer with the rounded off outside edge was installed outward towards the axle nut. My question is does it matter which way the washer faces? It would seem to me that the side of the washer with the outside rounded edge would go inwards towards the frame. Or was it installed correctly from the dealer? In the photo I have attached you can see the side of the washer that is slightly larger diameter and has a rounded edge which is towards the camera. Thanks.

[-deuced-]

I have not seen an '18 that close but know what you mean about that type of washer. I believe the dealer installed correctly. The flat side inwards will provide a larger contact area between the clamped surfaces.

[Norton Commando]

I have not seen an '18 that close but know what you mean about that type of washer. I believe the dealer installed correctly. The flat side inwards will provide a larger contact area between the clamped surfaces.

I agree; flat side against the swing-arm is the way I would install it. The washer was manufactured by punching it out of a piece of mild steel, which caused the rounded surface on one side. Notably, a hardened washer in the same size will be flat on both sides.

Jason

[smoserx1]

ALL washers (that I have ever seen) have a flat and rounded side and the flat side goes against the "clamped object" (my made-up term).  The rounded side goes next to the fastener (bolt head or nut).

[Slider1950]

Yeah the more I thought about it the more I know you guys are right thanks for the help.

[Dan89flstc]

The washer is there to protect the part from the nut, put the rounded side toward the part, that way the sharper edge of the washer does not touch the part.

Old aircraft mechanic technique...