Am I correct in thinking EVO class is basically post 78 pre 85 but as stated no linkage, no water cooled, no disc brakes.
Essentially that is the mindset of the majority of the VMX community.
However under the current GCR's, any bike produced prior to and post 1978 (regardless of when it was built) can be entered in the class as long as it is was originally manafactured (this is where the OEM comes in) with drum brakes, an air cooled engine and the rear suspension was of a non-linkage design.
Which for Honda would mean up to and including the 80 model CR250R but for some of the European brands goes later?Correct.