My  250 Quad(4x4)slips when changing gears.Engin revs and it will catch up and engage but feels like clutch is slipping badly.What is involved in the fix?  

go to www.rjatv.com for a better than stock clutch kit at a really good price.
John has some good clutch kits and ships out quickly!!

once you have the new clutch kit
drain the oil
removing the side cover and then the pressure plate.
then carefully removing the clutch plates and steel seperator plates one at a time and stacking them beside you in the exact order they came out.

then reinstall the new clutch plates and steel seperator plates in the same order as the old ones.

reinstall the pressure plate making sure not to strip out the screws and that you have all of the pressure plate springs on.

then test the clutch via the lever making sure the pressure plates engages strong against the clutches and disengages when the clutch lever is pressed.

reinstall the side cover, and refill with engine oil, then test ride it.

if it slips then remove the side cover and adjust the pressure plate rod in the center of the pressure plate.

hold the nut on the rod and turn the pressure plate rod to the left and the clutches will engage stronger.