Yamaha DT125E 1977 Owner's Manual page 13

Clutch lever
The clutch lever is located on the left handle-
bar and disengages or engages the clutch.
1 • Clutch lever
Pull the clutch lever to the handlebar to disen-
gage the clutch and release the lever to engage
the clutch. The lever should be pulled rapidly
and released slowly for smooth operation.
Gear shifting
The gear ratios of the constant mesh 6 speed
transmission are ideally spaced. The gears are
shifted by using the change pedal on the left
side of the engine.