http://cyclerestorer.com/pages/show_model_serial_num.php?bike_model=YZ80D&manufacturer=Yamaha
Looks to be a 1977 YZ80D
I was hoping it was a little older, but will be restoring her just the same
The tank says YZ but I was told it could be older. Having no luck with matching up the number to a yz or jt. Any info would be very help full. Thank You, Chris