Did you replace the chain at the same time? Assuming you did, how did you set the chain length for you new setup?
Thread the chain around the big ring and largest cog without going through the r'der pulleys and pull taut. Add 1 1/2 to 2 full links (1 inside and 1 outside section = a link), trim the chain at this point and install it through the deraileur pulleys. This should help keep the pulleys off the cog.
__________________
2003 Iceman Challenge - 2:34:55 - 897 / 2,000*
2002 Iceman Challenge - 2:39:23 - 1093 / 2,186
2000 Iceman Challenge - 2:49:18 - 1516 / 2,153
*estimated