[HWYSTR455]

It's def not piston slap, I can attest to that, and have heard piston slap on a multitude of engines.

Although the cam gear was observed and considered not having a runout issue, that was a visual inspection, and could technically still have excessive runout. But that's a big reach there, I have never seen that, and I've done a lot of cams.

Looking closer at the vid where they turned it over with the dizzy out, not sure if it's an optical illusion, but the moment the starter is engaged, it looks like the cam gear kicks to the rear for a moment. It might show a little wear on the very corner of the tooth where it kicks out, too. Maybe slow the vid down?

https://www.youtube.com/watch?v=dDZKHIOGWcE

Maybe someone else can chime in and see what I'm seeing? That might explain the gear wear, but still can't see how that would cause a knock. It would have to kick the shaft over considerably, and consistently, and would need to have the shaft bushing worn out for it to go far enough to make contact. Or that's what I'm thinking.

More I think about pin knock, doesn't that actually change when you pull the plug wire? I think it gets quieter when you pull the plug wire?

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