Check out the great TY80 action shots with Brutus and the boys on these threads.
http://www.advrider.com/forums/showthread.php?t=574301
http://advrider.com/forums/showpost.php?p=21141891&postcount=423
http://www.advrider.com/forums/showthread.php?t=574301
http://advrider.com/forums/showpost.php?p=21141891&postcount=423
Useful parts sites.
http://www.bikebandit.com/houseofmotorcycles/yamaha-motorcycle-ty80a-1974/o/m7797
http://www.bikebandit.com/houseofmotorcycles/yamaha-motorcycle-ty80a-1974/o/m7797