Because I don't know your model, let's take the ordinary 125 model as an example. The diameter of the bead bowl on the steering wheel is 45mm, and the diameter of the locking nut on it is 32 mm No special tools are needed to replace the front fork (of course, special tools are better), only two openings are needed to reach the adjustable wrench of the above data.

Oh, this front fork can be repaired if you are interested.