The Yamaha TZ-750 Miler: a racing motorcycle steeped in legend and myth.
The legend is well-known, that Kenny Roberts raced one at Indianapolis and won the race, beating a pair of factory Harleys in a last lap lunge that lives forever as a summation of Roberts and that amazingly crazily over-powered bike.
American Steve Baker is astride his TZ750-powered Miler in the above image, taken in one of the early practice sessions at Indy that day. The angle and light in this image illustrate well what riding a dirt track bike with a 120 horsepower engine in the cradle was like. While the engine looks ultra-wide in this picture the TZ engine was actually not as wide in terms of girth as the parallel twin used previously by the Yamaha riders in US dirt track. The radiator is typical 1970s ‘barn door’ technology and the tiny tube frame was probably near maximum stress with a four-stroke twin inside the downtubes.
Baker spent a great deal of time building these TZ-Milers and said it wasn’t really until he brought his, built in Doug Schwerma’s shop, to a spot in Hayward known as a location for illegal drag racing that he understood what they’d built, or monster they’d created, if you please. Baker smoked the local king of Hayward street racing by passing the poor local’s z-1 based drag bike while his TZ-Miler stood on the back wheel for five gears.