My brother inherited an old (1969) Schwinn Racer with a 3 speed Strumey Archer and wants me to get it running (but still look rustic). It looks like it was kept outside for a so the cables are toast, but the Strumey Archer hub was covered with oil and brake pad residue so it cleaned up looking like I just took it out of the box and shifts the same so I decided to not to open it up until there's a problem; the front hub, headset and BB also turn smoothly but I'll probably service them (already did the front hub). The only issue is I have is figuring out how much oil is supposed to be in the hub. The manual says to add a drops every now and then, but doesn't how much is optimal or how to figure out how much in in the hub. Any info or suggestion are welcome.