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+1 to the above.


the silver disc surrounding the head of the drive side crank arm is press/snap fit to the chainguard - much like the hubcap on an automobile

the tip of a screwdriver blade should be adequate to pop it off

it is common on italian manufactured cycles with a chainguard for the fixed bottom bracket cup to be used as a point of retention

if you lack a fixed cup tool it is possible to inexpensively create a homemade compression type one with a large bolt, nuts and washers from the hardware store

the cup is right hand threaded so you will want to remove it by turning counter-clockwise

the likely manufacturer of the chainguard is the the Mazzucchelli firm



best wishes with your project and please keep us posted on the progress...


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