The 2 compression rings for my 2001 m600 do not look like the ones on Haynes or workshop manual. They look identical (square) on the face that meets cylinder wall , but on the piston side there is a "step" on the other ring. The one without the step seems a bit stiffer and I think it should go on top, but from my disassembly pictures I found that the one with the step was on the top and the stiffer one under it. The reason I pulled cylinders was oily sludge on spark plugs, ring gap was huge (nearly 2 mm). New rings are from ducati and identical to the ones I took off, they are black and say k-top on the topside. So does anyone here know which way im supposed to install these? Duc catalog tells me the part I got is 12120232A, which has replaced 12120231A.