Campagnolo Crank Compatibility 11 speed crank to 9 speed chain/deraillieur/shifters I need to replace my 9 Speed Campagnolo Racing T Crank with a new one which uses the power torque system. 

Is a 11 Speed Athena (or 10 speed Centaur) crank compatible with the racing t front dérailleur and the 9 speed Chorus shifters?

http://www.campagnolo.com/WW/en/Components/athena_crankset

Bike parts


Campagnolo Chrous Ergopower 9-Speed       
Campagnolo Chrous Brakes
Campagnolo raceing t Crank (needs to be replaced)
Campagnolo raceing t front derailleur
Campagnolo raceing t rear derailleur
Campagnolo Chorus Cassette 9-Speed
Campagnolo C9 Chain
I have used Shimano 10 speed cranks with 9spd chain, derailluers and gears. 

Without actually having tried it with the Campy components you list, I see no reason why it shouldn't work. The only difference between 9spd and 11 spd chain is the exterior width of the chain. The interior dimensions are identical (i.e. 3/32 of an inch wide, 1/2 inch long). 

The one issue you may run into is that the front chainrings may be slightly closer together
than a 9 speed crank. When you are using gear combos that involve the cross chaining on the small chainring, the extra width of 9 speed chain may catch on the larger chainring. 

The shifting may not be as precise and fast as an all 11 speed setup, but of all the parts of the drivetrain the front cranks are the least "speed specific" and the easiest to interchange.