I’ve just read a topic where someone was having trouble with the in-tank fuel hose. I have two BMW K100s and they also run internal fuel pipes. So… rather than buy the OEM pipes and spend a double fortune, the hose ratings are:
SAE30R10 for fully submersible usage e.g. the Cali 14. Don’t use SAE30R10 for external lines as it doesn’t like UV light and will sweat fuel. It’s not cheap - if you can’t find it locally or online, Motorworks (BMW dealers in Huddersfield) will sell you some.
SAE30R09 for external use. If you use it internally it will soften and fall apart; it dies fastest with E10. Available almost anywhere.