You can make lots of things fit that were not intended. I had a 150/70-17 Shinko 705 mounted on my Buell Ulysses in place of a 180/55-17. It looked funny, but rode and handled pretty good. So I would think that you could replace a 150 with a 140 w/o any issues.
"I refuse to tiptoe through life only to arrive safely at death"
2006 Triumph Sprint ST (for sale), 2006 Tiger 955i(sold), 01 XR650L replaced by a '13 KLR 650, and a 2010 Honda NT700V for the wife.