Originally Posted by
Choke
Thanks. Yes, it's a grease fitting...there's also one on the BB, you can see it in the pic behind the RD cable.
Actually they're oil ports. Yhe significant difference is that the head and BB are not closed to the frame. If you use a grease injector on these, you'll (if you get carried away) pack the entire frame with grease.
OTOH, if you use the ports to inject a drop or two of oil, it'll refresh the grease, and extend the lube cycle.
BTW - if the OP replaced G40 rims with Nisi, he moved them closer to the original, which were like Nisi. G40's didn't exist when that bike was built.