250 CR 1994 Fork rebuild : "back up ring" direction ?

Hi, i'm about to rebluid my fork and i dont know the direction of the "back up ring"

The part sits between the upper tube and the il seal , part 10 on the scematic:


It is not the same shape on both sides. One is flat (on the left) , the other has round edges (on the right)

flat side.jpg round side.jpg

So i can't believe they made it like this for no reason but the manual dont say a word about the direction.

So i can't believe they made it like this for no reason ...

IMO the shape comes from blanking it instead of turning it on a lathe, which would be an accurate plate

purpose is supporting the bushing from the seal rim

Edited by kawamaha

thanks, you're probably right !

But since it also prevents the seal to distort, i'd would be better to put the flat surface agaisnt the seal, right ?

But maybe i'm a bit maniac when working on my ride...

as far as I rember it's mounted that way..

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