Matching case numbers

[Yami-Rider]

Cleaned up an old set of engraved cases, don't know the history, and it's been a while since I've looked at some engraved cases, but I'd assume the engraving should be the same top and bottom case?
The "7" is also different hand writing, so I don't think these are matching cases?
second number may be 57

 

[TheBuzzard]

I've seen and had a bunch of mismatch cases. Yamaha are pretty forgiving on needing to be a match. Kawi are more critical. All that is really required is when they are assembled with crank, that there is no binding and everything spins free. Sure is a nice option to just throw a used bottom without a hole on some nice ported uppers.

 

[Yami-Rider]

I tried non matching cases years ago and the center crank bearing failed 30 hours later

I just remember I had some engaved cases in one of my skis, sure enough, matching numbers.

 

[kevbo]

Check the hole size and lateral location if they arent a match set.. Many of these have been reassembled after being mixed up without failure. I want the hole to be correct regardless.