John those Servis tyres appear to have the same tread pattern as the Dunlop K70, But I have no experience of them, But so do the 350 19 Cheng Shin which I've used for years on my M20 my BSA/Indian and my Indian 741.(18" wheels)

https://www.vintagetyres.com/cheng-shin-c180-universal-350-18-1069

Ron

email (option): ronpier@talk21.com