I recently purchased the complete set of the 12 "Bomba" movies starring Johnny Sheffield whose picture is at the beginning of this site. They were made when he was between 18 and 24. His personality is very engaging in all of them. His loincloth is rather brief. It shows off his fine body very well. It is the only thing he ever wears in any of the movies.
Back in the 60's the Bomba films were shown every Saturday morning on a local TV station. I think I saw the Bomba films before any Tarzan movie. Sheffield wore the loincloth well and appeared comfortable in the role, and also seemed to take the part seriously. It's too bad that the TV pilot he did called "Bantu the Zebra Boy" did not sell.