Kawasaki G4TR

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99cc. The G4TR was the evolution of the first rotary valve single cylinder Kawasaki's,starting with the little J1 85cc street bike in the early 1960's imported into the USA.It's roots are more akin to the GA and G3 series that came a bit later although.

 This was the first of the small singles (to the best of my knowledge) to use the aluminum cylinder with cast iron liner for superior cooling like it's bigger counterparts,the F3 "Bushwacker",F7 175,F8 250 "Bison", F5 350 "Bighorn" and it's racing brother the mighty-mite G31M (chrome bore).

 1970 was the first model year for the "Trail Boss" 100cc, 10 speed.The high/low ranges of the main 5 speed gearbox are selected by a lever on the left hand engine cover,eliminating the task of switching rear sprockets as was more common on earlier street-trail and enduro machines.

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