[nelly]

There has been a change in SC but whether or not the pushrod was changed I couldn't tell you for sure.
I have a 748E in at the moment with the new SC and the pushrod on that is 326mm long.
There are different length pushrods, but as I said, I couldn't tell you for sure if they are a result of the different SC's.
The slave cylinders I have had made seem to work OK whatever bike they've gone on so I don't know why the Tecmoto product should play up??
Is your pushrod OK. They have been known to snap, in isolated cases, around the undercuts where the two o-rings sit.
Only other thing I can suggest is to check the master cylinder is returning OK.
There is a small screw that adjusts the amount of free play on the lever.
There is a "trick" to screw this in to gain a little more cylinder movement, but if over adjusted prevents the cylinder returning properly. The cylinder then pumps up and prevents the pressure being released when the lever is let out.