Topic: rear brake plate

[stresssolutions]

Don't really know what else to call it.  The piece that the shoes mount to, the axle hole has some grooves in it, they are across frome each other, and extend most of the way into the hole.  They seem to be tapered, see pics. 

Is this odd, unusual or normal? If it is unusual, is it bad/dangerous?  What would have caused it, if it is unusual?

Thanks.

[HavocTurbo]

Mine has that..... so did my yamaha and kawasaki back plate as well.

I suffered no ill effects.... but who knows.