Hard to tell, but that is an excellent resource.

I suspect this bike might be a bit older, as there is what appears to be a date stamp on the crank from 1998. That would place it as maybe an RL140? Except that the component mix does not match exactly.

This thing has no decals on it, but then those aren't that reliable anyway.

There is a serial number stamped on the bottom bracket. Is that something that can be decoded, like the VIN of a car?