One useful link for this query might be
http://www.british-forces-motobikes.....uk/index.html
I found a photo of an M20 in Egypt at:
http://www.commanet.org/Media/large/014r00f60as5.jpg
"R.A.F. Abyad, Egypt, Billet D5. Motorbike is a single cylinder B.S.A. M20 500cc side valve Ex War Dep "
Mark.