[Graham]

This is a great list!! Almost easier to list motors not allowed.  You’ve done a lot of testing wow!!! So my class B Event 2 car spins a Scalextric, slimline that is less than 23k is that ok to run or do I need to run a differential 

If it’s the current Scalextric slimline std motor it is classified as a 18k rpm motor, and hence a Class A motor. As it stands any other Scalextric ( green or red) slimline motor with a higher rpm is classified as a Class B/C motor depending on whether it is fitted into a Class B car ( modified or scratchbuild), or even a Class C car ( ProCar), which I guess is less likely, but possible.