I am in the process of building up a Colnago Pista with a Cinelli Alter stem. The problem is that with the stem tightened all the way down it still slips on the steerer tube. According to the instructions you should use 13 Nm torque which we have done. Also it seems like the threads could get stripped out if the bolts are tightened any more. This is a brand new unused stem. My bike tech said he has checked the measurements on both the stem and fork and said they look to be within the specs. I found where someone else was having the same issue and ended up using a can as a shim to get it working here http://www.bikeforums.net/singlespee...stem-help.html

Any ideas?