Doing this job on a Yamaha XT225 Serow is easy. Just a couple of things to bear in mind...
1: The friction plates may not be seem badly worn, but can lose grip through becoming glazed. Put the plain steel plates together and check they are not warped – another cause of slip.
2: One friction plate is narrower than the rest. It goes in the centre of the pack and accommodates a spring-steel wave washer that helps separate the plates and prevent rattles.
3: Drive notches must engage when the pressure plate is fitted over the spring pillars. Don’t worry if alignment marks are missing; there are just four possibilities and it only settles home on the right one.
4: Thicker new plates may affect pushrod adjustment – they could also make the clutch heavier because they effectively shorten the compressed length of the (non-adjustable) springs.