The only thing I know of is wear in the clutch basket - I'm assuming you didn't change this when you changed the plates?

The basket is alloy, and it will wear over time until there are notches in it that prevent a smooth action. Have a look at the fingers where the plates pass the torque accross, and it may simply be that causing the notchiness.

You may be able to file any slight wear out, if not it'll need a new basket.

Keep us informed!
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