The crank on the left is an IFMA EFRA spec crank. The one on the right is a BRCA or non modified crank. EFRA changed the rules for this year to allow modified cranks but the BRCA and others such as the french are lagging behind.

Novarossi still have these cranks in staock so are trying to get rid of them. I suggest you return the motor and ask for the correct spec.

Cheers