You could be onto something there. When I look in the riders handbook, early models (don't have the later book, though my bike is) 220 is close to redline in fifth, 150 is close to redline in third, but 50 isn't close to anything on the graph.
I spose I'll put it back into the file of "Things I know I shouldn't wonder about but do"
I spose I'd have more replies if I made a separate thread on it, but then I'd have to take it back out of the file that I shouldn't even be looking at.