Considering that the TZ was the most significant readily and affordable to many available competitive racing machine in the past 50 years I am surprised at the lack of interest in this topic.
Seems that there is more interest in who is related to who or how they might have started in racing.
The TZ series of racing machines manufactured by Yamaha form 1973 to its' sad demise in 2006 (ish) were arguably the machines that led to the best era of motorcycle racing, from club to GPs that ever existed or will ever exist.
It can be argued that the TD2 and TR2 were even more significant because they were the first of the production racers that could be purchased by the public form your local Yamaha agent on which riders of non-works exotica could challenge the established front runners on their works machines.
What an era they led to. I well remember the days when you'd turn up with a 350 TZ to find 120 others vying for a first 14 in the 5 lap heat to qualify for the final.
National standard race meetings almost every weekend with more than one club meeting every weekend in the season. At least at a club meeting more than one 5 lap dash was guaranteed.
Ask 'top men' of today what they would have liked to race - a 250 two stroke grand prix machine.
Never see it again - sadly