Many topics about this on this forum, but heres a question.
In my 1990 RM125 I just put in the required 650ml of tranny
oil, when you look into the oil filler hole the oil level is nowhere near the top of the case. Many threads on this
forum indicate the safe level is when the oil just starts to
drip out out of the fill hole. Any clarification would be
helpful.
On my 89 Rm 125 there is a bolt on the water pump side that you can take out and when oil starts comming out of the hole you have enough oil in the case.
The oil is not gonna be anywheres close to the top of the fill hole.