My DT125 reads 'DT125E' on paper...and fondly refered as 'Yamaha Enduro' by the public. The 'E'signifies Yamaha's CDi ignition system - I guess it's the same bike as the DT125MX in UK? Back in the 80s, the monoshock was one off amongst scramblers, a pride!
Although a dual-purpose type, it can be seriously good for motocross-work. Mine was stripped left only the head&tail light. A YEIS induction from the street RX-S was bolted-on for better torque. Next was a bigger exhaust-system+carburettor -jetting. Knobby 'cross'tires. Eventually, it was 'upped'175cc by a simple used 175 block & piston. The primary & secondary sprockets were 13/52 if I remember. Wheelies in 3rd gear!
Around town it was fun, able to run with street RX's till 4th gear! People at the bus stands would cheer on when I rode up the pathway during traffic jams. On weekends, at the dirt track, some RMs & YZs could be trailed closely or even passed, depending on the rider!
For me, my youth means my unforgetable... Yamaha Enduro. I wasn't rich in money then, but truly a rich, exciting life! Mud, sweat & gears.... Period...