Thank you Marnix for the reply; what is the internal and external diameter used at the time for CLAVIS BENZ fuel lines ? Was the CLAVIS brand white on the tube ? Is it correct that there are screw clamps and not "clips" in your photo to lock the fuel lines ?These Cavis Benz fuel lines have been on my SFC for over 30 years now. As you can see their green colour fades, but they still function and when the engine gets hot, they still become fairly flexible. The hard part nowadays is to get hold of the proper material..
Marnix
Yep ... at the July motorcycle rally in Breganze I saw some perfect silicon green ones!I've also got old CAVIS BENZ stuff fitted to a couple of bikes, softens nicely with heat and once fresh fuel travels through!
Most modern stuff discolours, shrinks and goes hard...
Silicone fuel line may work, but I've never found any in suitable sizes or proper shades of green.
piet
No PVC-based fuel line is very durable when used with modern fuels, they discolour and/or harden within 2-3 seasons. Several blue and greenish ones available, non work very well. At least I haven't found one...

Blueish green?the spare left on the reel in a dark indoor cupboard is now BLUE! what? how can that be???
CLEM