Campag "rear derailleur cage return spring" tension setting?

[th0m]

I was cleaning an 8-speed Record rear derailleur the other day and removed the cage among other things. When I assembled it afterwards, I noticed there where two holes where you could put the end of the return spring to either increase or decrease the tension. I didn't pay attention to where is was originally, so I ended up using the higher tension.

Could someone educate me about the purpose of this function and was I correct in mounting it in the "high tension hole"?

 

[jim haseltine]

The normal setting is the lower tension hole - at least that's how the mechs were set in the factory. The higher setting is there for use if adjustment of the B screw won't allow the body to sit such that the upper pulley is positioned correctly to the teeth of the larger sprocket.

 

[th0m]

Ah, I see, good thing I asked then. Thanks for the help, really appreciate it.

 

[Nob]

Lower tension also result in less friction so saving watts