OK, I'm not strickly following Zen's rules, but my first "steet" bike was Yamaha YG-1 (1963?), c/w GYT kit (modified rotary valve, bigger carb, high expansion chamber and ported cylinder?).
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Lights were stripped, set up as a dirt bike, but I did ride it on the street on the way to the bush.
1st bike I rode on the street was a 1972 DT-1, orange tank, similar to this:
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But my first REAL street bike was a 1970 H-1 Mach III Kawasaki
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Mine was a blue tank.