Cloned copy of first gen;
To my knowledge they're on the third release, the first looking very much like the second just w/o the side plate reinforcement (the cloned Chinese copy w/no reinforcement at all is a copy of the first gen). Side plate flex, lateral alignment & complexity still being somewhat problematic with the second, they came up with the third, the "one piece" design currently available...
I've a second gen on my '43 & while I love it, so much in fact wouldn't build another motorized bicycle w/o a jackshaft - plate flex under heavy load & abusive riding can lead to the cross shaft eventually "walking" out of the bearings, lock collars notwithstanding. It's just a maintenance issue and can be modded to prevent this problem - but the third gen's shorter side plates & unitized design should fare better *shrug*
Second generation, bearing plate on the left side has reinforcement, right side (2nd pic) has no reinforcement, motor mount plate & side plates being separate also allows flex, small L bracket included to affix engine mount plate to right side plate insufficient to prevent flex entirely, metal fatigue caused L bracket to snap eventually (aprox 4000 miles);