Pre-81 doesn't catch anything we don't want, apart from the '80 model KXes.
The 81+ bikes that we DO want fit into the "certain Pre-85 bikes" bit.
I'm just kicking around ideas of how to cleanly exclude YZ-L forks, Simons USDs, etc. Defining it as "Pre-81 plus some" seems like the best way to kill off those things (and the SexMax).