what do the fingers on the clutch basket look like? If they have notches, that'll cause grabbiness. If they're not too deep, you may be able to get by with just filing the fingers smooth. If that doesn't work, I'd recommend a Hinson clutch basket (or similar billet product)
There are three pieces you need to update 1. Special friction plate
2. Large washer
3. Large conicle shaped washer.
What it does is go between the first and second friction plate to keep the plates from sticking to the clutch hub. Actually the new friction plate you buy will allow both washers to fit inside of it. Inside diameter is larger than the stock plates. All the pieces are OEM from Yamamha. Just look at the fische and you can see what and where they go. ten minute fix no more grabby squeaky clutch.