Clutch Rod Sliding UP For Some Reason?
 

After replacing a clutch slave cylinder for the second time, I noticed that when I work the clutch, the rod that actuates the clutch starts sliding up and the clutch pedal will no longer go to the floor. Obviously a bind. If I hold the rod down in place with my hand it works fine. At the risk of asking a dumb question, does anybody know why this is happening and/or is it going to require pulling the transmission. As it is, I can't drive it.
This is a 2003 R50 with the slave cylinder on the top rather than underneath the transmission.

Thanks in advance for any reply's.