little ball bearing (in Aisin hub)
The little ball bearing in the Lock/Free selector of the Aisin manual hub is obtainable. I inadvertently lost those little balls when I was disassembling my hubs. I found replacement ball bearings at a bicycle shop. Bicycle shops use different size ball bearings for the headset race/bearings and manually drop in the little ball bearings. I brought the selector part from my hub, with the spring in it, to the shop and had them find the best fitting ball bearing ... it was 11 cents per ball, 22 cents for two! I have NEVER purchased a part for my 4R so cheaply! : ) So, no need to worry if you lose that little ball.