Recently the gasoline hoses of a re-aroused classic once again dripped off the gasoline. Ordinary, classic rubber gasoline hose is not resistant to the 'new' gasoline.
And in another case, the rubbers in a set of Dell 'Orto's turned out to be a sort of ragged snot after a season. But the excise juice is also aggressive towards (light) metal and cork. If the fuel hose on the outside is marked with "FUEL" or "FUEL" or something similar, it is suitable material. Other rubber parts such as membranes from a mechanical gas pump should, for example, be made of nitrile rubber or viton. Throttle passes in carburetor housings can be cork. If they start to leak, you will get false air and the engine will go to waste. New bearing of Teflon vans is an excellent solution. This is an intensive job (usually a complete carburetor overhaul) of dismantling and assembling the carburetor (s) and fully adjusting it again.
the word Membrams must be Membranes!
Is right !!!