Early in 1969 Yamaha acknowledging the popularity of the 125cc GP class of roadracing, released a limited number of GYT “hot up kits” to suit their AS-1 road-going motorcycle. The kits consisted of barrels, heads, pistons (longer to suit higher deck height), rings, exhausts, racing magneto ignition, carburettors, con-rods, big end bearings, clutch plates, a pair of gears (alternate ratio), gear change lever, clip-on bars and a racing twistgrip.
An interesting side note… Yamaha also released a GYT hot-up kit for their 100cc YL-1 twin cylinder roadbike in 1969. Next from Japan came a similar kit for the new AS-3 roadbike including, once again barrels, heads, pistons (shorter to suit standard deck height), rings, exhausts, racing magneto ignition, carburettors, con-rods, big end bearings, clutch plates, gear change lever, clip-on bars and a racing twistgrip. This time around it also included gear components to bring the bike up to a 7-speed. Nothing except con-rods, rings and gears were interchangeable with the AS-1 kit to fit an AS-3 or vice-versa.
