strange thing that spark plug at rear cyl is oily ??
The motor is a newbuilt stroker (t&O flywheel and pistons)
Front cylinder is nice when i check the plugg.
Compression is good on bouth cylinders when cold
Had to file down 0.30 rings to 0,20 pistons, and it wasent perfekly strait but in tolerance..?.
can it be the cutout i made in bottom cylinder skirts for clearance of rods?
Anybody recogise this problem??