An engineer’s perspective
Australian Rod Tingate was working at Yamaha’s European headquarters in Amsterdam at the time of the launch of the TX500 (and the previous TX750) and was part of the team charged with ironing out the numerous bugs. Here is his tale of the development saga…
“Late 1973 saw Yamaha’s test and research section organise factory engineers Takeshima, Okuyama, and M. Suzuki, to investigate the developing overheating and mechanical issues of the TX500 engine. The team arrived in Amsterdam where Yamaha’s technical man, Bob van der Zyden, had gathered a group of test riders and mechanics. The first TX500s had been tested at Yamaha track facilities in Japan, with relatively light Japanese test riders. Engine overheating, and oil leakage around the cylinder head and rocker cover did not become obvious. It was Bob’s idea to test with heavier European riders on the actual autobahns that they were to be operated on. The team and bikes were transported to a small village in Germany, to a classic hotel situated just below the historic Griefenstein Castle. This would be their base for the next three weeks. The bikes were ridden at high speeds along the undulating German autobahns by Dutch endurance race-riders including Jan Kostwinder, from early morning to late afternoon. After 500km of sustained full throttle running in the morning, and another 500 km in the afternoon they returned to the makeshift hotel basement workshop. The mechanics worked late into the night inspecting the bikes for cracked heads, oil leakage, and other associated problems, before preparing the bikes, and the test equipment
Yamaha factory personnel equip one of the TX500 test bikes.