Anyone recognize this washer?

[kawabunga]

I took the clutch cover off my ‘79 and discovered this washer at the bottom of the engine case below the crank. It feels like it has a little lip on it like it was compressed. The one photo shows the spot I found it. Any ideas where it’s supposed to be other than floating around in the engine?

 

[5twins]

I don't know if it's the right size but the tach drive rod has a shim washer fitted to the bottom of it (#8 below). It shims out the up-down play in the rod but also spaces the rod up away from the case so the spinning gear on it doesn't grind into the case.

The size is 8mm I.D. x 11mm O.D. x 1mm thick.

 

[kawabunga]

I removed the tach drive from this bike so I think that’s a likely suspect. Probably fell off an I didn’t even know it was there.

This washer is 12.2mm O.D. x 8mm I.D. x 1mm thick. I dug out the tach drive and it fits on the end nicely and the drive splines fit into the area of the washer that looks like it was compressed. I’m guessing the drive splines wore into it.

I’m gonna call it mystery solved!
Thanks for the quick reply, 5t!

 

[Mailman]

That was a good bit of sleuthing!

 

[kawabunga]