Theres a little sprung plunger which pops the engine cover up when the catch is released.
Took the plastic cover off and undid the nut an locking nut at the bottom of the plunger. Took it apart and found no lube and a bit of rust on the spring.
Packed it with grease and bobs your auntie!
Having just got back from Le Mans, and ready for some sleep, I have removed this in case you are right Chris. I suppose every time we try to have a laugh, now we have to think of sponsors.