It isn't really practical to work out why Honda uses a different ring design in the GCV160 compared with the GXV140. In the case of a modern car, making the substitution blindly would be a bad idea because of problems like ring flutter which may occur at a specific engine speed. For a small light-duty mower engine, which runs at quite modest speeds and accumulates relatively few hours under load, some minor ring malfunctions might be insignificant in practice. So, now that you have volunteered to be a guinea pig Mark, you may find out on behalf of all of us, whether the substitute rings last as long as rings of the correct design. That is if you keep the mower yourself and accumulate a couple of hundred hours of use of it, of course.
