Fuel lines

[Captain Black]

I'm going to change the fuel lines on my 80 GS Basic. The cross over line that get's threaded under the airbox looks a different diameter. Are...or should all the lines including that one be the same standard fuel line diameter ? I bought my new fuel line from motorworks as the original has some cracks starting, especially that cross over pipe that looks like It might not be the standard stuff anyway. I assume that just a pull's out and thread the new line through under the airbox ?
Thanks.

 

[Beemerboff]

The writing on the crossover line on my GS is still visible - it is branded BMW and the size is given as 6mm x 11mm, but you will find it difficult to find either BMW branded hose or 6 mm x 11 mm.