Just looked it up and it had a 4" stroke... so it wouldn't surprise the orientation was to prevent the bike becoming too tall.
That is a lovely looking bike, looks exactly like the one in that transport yard except his/hers was Black. all over.
it was exactly this, i know containing engines within an allocated space is a pain for a designer, you will remember how some bikes could suffer with front tyres touching water rad on extreme braking as packaging limits so small at times.
yes, and more besides - was talking about the precise angle that was all. This varied slightly even within the Panther range i believe.