In my digging into info re the lightening of flywheels I see that Vizard says that they weigh 28lbs/12.7Kg with 1300's being 32lb/14.5kg. (includes backplate) I presume he is refering to English made flywheels.
I have two flywheels I'm considering to use, one is a solid one the other a two piece and I presume Australian made. They both weigh 10.0Kg or 22lbs. Vizards says to aim for 18-19lbs/8.2-8.6kg
It appears on that limited observation that Australian flywheels are "halfway" lightened ie falling halfway between the English made flywheels and Vizards recommended for modifying original.
I intend to follow the Doc's advice and take 0.200" off the back of one of them(probably the solid one) and will let you know how much lighter it ends up.
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David L
My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!