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No. And honestly,you need both cases in order to work properly since they are a matched set.
 

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You should listen to me. No, seriously, listen to
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K9 and later is a 2 piece crankcase vs 3 piece for the earlier years. Basically it's a completely different design so there's no hope. Even if there was, OG is right. The pieces are a matched set and shouldn't be swapped around.
 

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That’s Mister Chalet To You ....
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I've read this many times out here and while I'm certainly not arguing, I'm just wondering: what is it that makes them matched? They're two separate castings that get cleaned-up and machined, then mated to each other during engine assembly. What assembly process results in them being matched with each other and incompatible with any other upper / lower?

I CAN imagine a few things like manually drilling holes that have to line-up and other things that I'd be laughed-at for thinking were part of building a gsxr engine.

If there's an old thread explaining this, that would be cool to read-up on.
 

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You should listen to me. No, seriously, listen to
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^It's important that the upper and lower halves of holes like those for the crankshaft exactly match with each other. Normally the manufacturing strategy is to use pins to establish a unique upper/lower fit, then assemble the halves and machine the holes in the assembled parts. The components from different assemblies will fit together slightly differently, which is not good for those critical holes. Your statement "two separate castings that get cleaned-up and machined, then mated to each other during engine assembly" misrepresents what happens, i.e. they actually get mated first, then machined.
 

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The cases are line-bored together to ensure crank journals match. I know machinists(my engine builder)that have utilized two different case halves on a Busa and machined them to work together but its a significant job which requires machining larger bearing surfaces and then taking time to make each sure each one is sized properly.
My guy has done it,cause thats his profession and it was for his own bike.

Sometimes this will not even work as the case halves are too mismatched where the crank sits and maching to fit is not possible or feasible due to time/labor/effort. Cheaper to buy a used engine and go from there.
 

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That’s Mister Chalet To You ....
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Fascinating. It would be cool to see these processes in action.

There's a french expression that comes to mind. Loosely translated: I'll go to sleep a little less stupid tonight

Thanks to both of you :cheers
 

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^It's important that the upper and lower halves of holes like those for the crankshaft exactly match with each other. Normally the manufacturing strategy is to use pins to establish a unique upper/lower fit, then assemble the halves and machine the holes in the assembled parts. The components from different assemblies will fit together slightly differently, which is not good for those critical holes. Your statement "two separate castings that get cleaned-up and machined, then mated to each other during engine assembly" misrepresents what happens, i.e. they actually get mated first, then machined.
The cases are line-bored together to ensure crank journals match. I know machinists(my engine builder)that have utilized two different case halves on a Busa and machined them to work together but its a significant job which requires machining larger bearing surfaces and then taking time to make each sure each one is sized properly.
My guy has done it,cause thats his profession and it was for his own bike.

Sometimes this will not even work as the case halves are too mismatched where the crank sits and maching to fit is not possible or feasible due to time/labor/effort. Cheaper to buy a used engine and go from there.
:fact:fact:fact:fact:fact. Exactly what these two said.

You don't even want to interchange the cam caps from a different case set.
 
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