I have a 1608 that i want to rebuild. I measured the pistons at the bottom skirt at 79.94mm or 3.147 inch and top of piston is 79.5mm or 3.13 inch and the bore is about 80.5mm or 3.152 inch top and bottom. i have .55mm clearance between piston and cylinder at the top. Is this normal for this engine and if not what has worn the piston or the bore. The bore is 80mm to start so it does not seem to have worn much. I am worried about piston slap and compression and am wondering if i should have it bored out. Also after a quick hone i noticed that the top piston ring has worn a groove in the cylinder wall at TDC. I guess that means a rebore?
Thanks
Dom