My Father In Law bought a "1979" NOS license plate nearly ten years ago, before California changed the YOM (year of make) laws to include 1970-1980 blue plates, and he gave it to me when he gave me his bike. After I received the bike, I transferred the title and applied to use the plate. The DMV kept telling me the plate was clear, and unregistered, but they also said the system wouldn't take the plate. I received my new title this week and didn't receive new stickers, and I called the DMV and found out the vintage plate was STILL unused (meaning It wasn't applied to this biket). So I did a TON more digging and found this website: http://www.allaboutlicenseplates.com/motorcycle.asp?State=California It clearly states that 7 digit plates only existed in the mid 80's. Also CA has a new application (that neither the DMV or myself could find in October) that states non commercial blue plates can only have 6 digits. So now I have purchased another 6 digit late 70's plate, and I have ANOTHER appointment to re-plate the bike. This website doesn't come immediately when scouring the internet, but it includes straight forward data on how License plates for cars, trucks, trailers, and motorcycles were numbered over the years.