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750K0 Lower Crankcase casting

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AshimotoK0:
Anyone know what the purpose  of the 750K0 Lower Crankcase casting circled in red  is?

it appears to be  broken off at the top on my 69 K0 crankcase.


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MrDavo:
I can only guess that it’s an oil guide vane to make the oil go to where the engineers wanted it as the crank rotates. The main bearing shell has a tang to locate it, so it can’t be that.

Is it not there in later engines?

Trigger:
They snap off a small bit at the top when the chain hits it, about 40 out of a 100 engines I do have it broken  ;)

AshimotoK0:

--- Quote from: Trigger on August 07, 2019, 05:35:36 AM ---They snap off a small bit at the top when the chain hits it, about 40 out of a 100 engines I do have it broken  ;)

--- End quote ---

Thanks Graham ... should I try to repair it or is it OK to leave it? There was no alloy bit in the engine when I drained it and the tensioner looked like it had recently been replaced... but I got a new one and chains just in case.

This is mine & the damage:-


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K2-K6:
Generally things like that are part of "windage " mitigation that engine designers use.  It's to try and peel off excess oil from rotating crankshaft to prevent a rotating oil mass building up round the crank. 

Where oil comes back down from the head it drops onto the crank more than other extremes of crankcase, so it tries to seperate it to push it down toward the sump usually.  A bit like a potatoe peeler.

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