Fuel Tank

One thing (there may be others!) that has puzzled me is the absence of a crossover tube on Amelia's fuel tank. It seems to be a fairly well established fact that Solex-equipped Square Fours have one fuel tap, with built in reserve, on the left - because a tap on the right is in the way of the Bi-Starter knob and could drip fuel (they don't leak, do they?) on the distributor.

These first three pictures are all 1951 SQ4's, like Amelia:

Left hand tap (also note the brake lever stop! never seen one of those before) 

No right hand tap, no crossover loop. this bike has a drain point at the RH front of the tank, like mine

Obvious crossover loop

Amelia has two petrol taps, one drain point at the front, just like this 1952 KH

Left hand petrol tap, no crossover loop

Right hand petrol tap, no crossover loop

So... What do y'all think of that?