Often the Keyed washer is forced to turn by the lock nut turning, , Digging into the fork steerer thread,
(I have used an aluminum <c> 'super record' spacer, the thread scored the tab instead)

Adding a non keyed spacer is fine, [Maybe better as it will spin rather than the keyed one] It just has to be close to 1" inside diameter..

I have used steel tubing, as spacers... and even used the Shop fork threading die to cut more thread..








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