piston/cylinder sizes

I know this will seem to be a dumb question, but I am rebuilding a kawasaki 650 engine(76mm stock). I have a new cylinder that is 77mm. My question is if i buy 1mm oversize pistons will they fit into the cylinder or do i have to have it overbored?

Your piston to cylinder clearance is critical. You can use a feeler guage, slide it in between the piston and cylinder, divide by half, post what your clearance is. BTW, what kind of pistons?
Joe........

Well first off i bought the 89 kawasaki 650sx used and i have never ridden a stand up or taken apart an engine but have been boating all my life. I put a new battery in and cleaned the lines and tank and fired up after a couple tries, but ran very rough and also the battery did not charge. The next day it wouldnt fire up so i took off the head and found part of the piston was missing. So i took the cylinder off and found that one sleeve had a major gash in it. I then proceeded to buy a used cylinder on ebay for $35 and all it needs is honing. The measurement on the cylinder is 77mm and I have yet to buy a piston kit because i do not know what size pistons i should get in order to avoid boring the cylinder. I was looking at possibly wiseco or WSM kits

also since it was not charging should i replace the rectifier and charging coil or the rectifier, charging coil and exciting coil?

I would send your cylinders into a machine shop and have them tell you what size pistons you need to order. Check out Robert Sand and www.jetskimechanic.com You could send your cylinder into him and he will get you the exact pistins you need. Also, you could send in your stator and have him test it. This would take a lot of the guess work out of the picture:)
Joe........

Thanks, this site has been so helpful :D