I see what you're saying but pulling the barrels off, replacing the pistons, rings, little ends and every gasket along the way is not "preventative maintenance", it's a top end rebuild and £170 on bits into the bargain.

Whatever you're trying to prevent with this maintenance is irrelevent, you've replaced 90% of the bits that could possibly have been damaged and probably spent far more than you'd have done to get it running again if some component had failed.
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