Reply To: Neural switch replacement – GT125R
It would be a wise call to change the O-Ring as the old o-ring will be caked up due to heat fatigue , so it won’t seal properly next time it goes in.
No need to drain the oil, BUT a “tiny patch” of oil will come out, simply because behind the switch is a camshaft drum for the gearbox
Take it out SLOWLY! = There is a spring and pin behind the switch too.
IF you need the O-Ring , here it is:
Neutral Sensor (Gearbox Switch Drive) O-Ring Seal – Various Hyosung Models