Hi Raj
I am Irish so there's a drop of water in the way
However brexit permitting I am hoping to go to Stafford at the end of April to the show
You are not far away from Cameron Engineering, a chat with the "Dad" there might give you some info on your engine
Post WW2 J.A.P continued to make competition engines as well as industrial units
As far as I know only one post war road bike featured a J.A.P engine ?? AJW
John