Excessive topping out inertia resulting in bent linkage plates... a fooked shock (sans oil) will definitely be a BIG factor as there won't by any rebound damping to speak of at all. As a matter of fact, the Sachs shock has woefully poor rebound damping straight out the box, never mind when on its last legs! So it's probably been smashing into the top-out bump stop for many a mile, giving everything else in the linkage a right old hard time of it.

Glad you've got to the bottom of it!

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