well on my 87 yz125 i take the drain plug out of the bottom of the motor to drain it then put it back in... then there is a little black like cap by the kick starter where you put the oil back in i use gear saver for mine...
No
30:1
Yamalube motor oil.
32 to 1
No oil filter, the YZ125 is a 2 stroke.
135mm (80-150)
4ozs to 1 gallon
Yamalube Trans Oil. You should be able to get it at your local Yamaha dealer. ROCKETMAN
2 strok(gas mixed with oil)
no.
top speed of a yz125 in mph
whenever it is fulli use 1 and a half quarts in my 03 yz125