Hello to everyone,
What wonderful detectives you all are. 
Kate, thank you for the clean up of the picture. Just great . 
Dudley - thank you for your information and the link to the vintage bike site. I think that is the bike in my picture. 
Old Rowley - Your information about the bike being a Coventry Eagle and being registered in Nottingham(shire) 1921-55 is very interesting. Thank you. 
looking for old - Great information about the registration plate. RR being 1930's and the tax disc information. I would not have thought of that. 
It is the person in the front seat who is of interest and could be a relative. The person at the back is completely a mystery. The fact that Nottinghamshire is mentioned is good as the family were based in Staffordshire , so not far away.
I would like to thank everyone for their thoughts on this picture, I certainly have enjoyed reading all the information and I can be 99% certain that the person in the front seat is who the family thought it was. 
Again, many thanks to everyone, 
regards Meg 
 