Next to the YZ607 there was also the YZ608, the 350 cc bike. This was a further development of the first try-out, the Z608, based upon the street YR1.
The 1967 YZ607 was an USA prepared factory machine, using various components.
The 1974 TZ750R was already very different from the standard TZ750.
This is the official picture of the 1974 YZR350 factory bike.
The Yamaha RA55 125 ccm was the improved version of the RA41.
The production of the Yamaha TZ500 commenced with the 4A0 model in 1980.