I am new to this forum and hoping someone can help me out. I have an early 2000’s (pretty sure its an 01-03) Honda 300ex, it has an aftermarket extended axle but don’t know the manufacturer and can’t find any markings to indicate who may of built it.

I was riding and lost a Castle Nut for the axle and can’t find a new one that fits. Does anyone know of an axle manufacture who uses a 20mm fine thread axle nut on their axles.

I have been to two Honda dealers here in Pittsburgh with no luck. I have tried part # 90304-hm7-a10* which is a 20mm castle nut but the thread is not correct and won’t thread onto the axle.

Please if anyone has any ideas or leads it would be greatly appreciated.

Micah