motobecane catalogue specs of different models ...

c.1974: http://www.flickr.com/photos/strongl...n/photostream/
c.1975: http://www.flickr.com/photos/strongl...n/photostream/
c.1976: http://www.flickr.com/photos/strongl...n/photostream/

from these, it appears the GJ model frame came in both red (w/blk) or silver. the GR frame came in both black (w/red) or silver. but i still don't know the exact date of my own GR. oh well...