Hi there I also have a yzf600r with extra motor I am building with a tight budget.

Simple question, How important is it to keep the pressure plates in the same order? This is a low budget bike, and if I can reuse the clutch for another 1.5-2 seasons, then I will be happy, as this is a beginner bike for a friend.

 

Its pretty important. You have to consider that these have been worn into each other. if you put them back in a different order, the plates wear patterns will not match up. You will more than likely experience clutch slip, or rapid wear of the discs.