Yes, for some reason the previos owner put a 500 badge on there, but I checked the engine and frame serial number and it is a GL400C indeed.What is your fork tube dia? badges on engine say GL500 but the bike looks like a cx custom. Or a franken-bike. no offence intended
Yes, the diameter is 33mm and they have air valves on top.Measure the chrome tube. I reckon they are the 33 mm forks and if so the fork oil spec will be from the 78 standard. 135 - 140 cc.
Thank you, I will add the info soon, and defenietly gonna check on the parts as well!BTW: Welcome to the forum.
The previous owner also said something about the Japanese domestic market, it supposedly came from there, so it might be the reason.It's one of the weird Asian/NZ market variants