1978 Yamaha TZ250 Motorcycle

Description

Yamaha's new production race bikes, the air-cooled TR2 and TR3, revolutionised road racing the world over from the time of their introduction in 1969, quickly becoming the benchmark in both Senior and Unlimited classes.  Using technology trialled by the ‘Flying Finn’ Jarno Saarinen in 1972 (who won the 1972 250cc World Championship on a prototype version), Yamaha introduced new water-cooled 250 and 350 models the following year and the TZ series ultimately remaining in production for the next decade.  The TZ250A had a bore and stroke of 54mm by 54mm, 7.6:1 compression ratio and Mikuni VM34SC carburettor for an output of 51 horsepower at 10,500 rpm.  The TZ250 and TZ350 were soon dominating racing across the globe, including Australia where Ken Blake won the 1974 350, 500cc and Unlimited titles on Yamaha's twins and his 'Coca Cola' liveried TZ350 is still fondly remembered by many local bike racing enthusiasts.  Yamaha made only minor changes to the TZ250B for 1974 but the TZ250C of 1976 incorporated a redesigned chassis with adjustable mono-shock rear suspension and twin piston front and rear disc brakes gave the new model a better ride and stopping power.  Relatively few changes were made to the succeeding D variant, although changes to the heads and new expansion chambers resulted in a small increase in power to 53 bhp at 10,500 rpm.  The TZ250E of 1978 had a new frame with detachable alloy engine plates and the motor itself was mounted in a more forward location.  Yamaha’s TZ road racers have a cult following around the world today and surviving examples are sought after by collectors and bike enthusiasts alike.