The DT2-MX has been omitted from Bikepics.com Yamaha listings so I have listed it with the street trail DT 250. This is unfortunate because this model was significant in Yamaha's history and archives. 1972 marked the year when Yamaha first produced engines with reed valves, called Torque Induction. This system helped deliver more low-end power and quicker engine response over the entire RPM range. All 1972 MX and Enduro models had reed valves, except the JT-2 Mini Enduro, which had rotary valve induction. This was also the first year for CD ignition, which came standard on the RT2-MX (360cc). Photo was taken 1972 - May time frame. Mono shock technology did not exist for rear swing arm travel. Note the rear shocks.