200x piston/cylinder Q?

[Yamaha_Rules69]

Ok, I have a Weisco high compression piston and rings in a box full of 85' 200x parts I bought a while back. I had two stock cylinders, and what that I assumed was one bored out cylinder, because it has fresh cross-hatch lines. On the bottom of the cylinder someone wrote 2.561 in perminant marker. I used a micrometer on the piston, and it came out 2.557, which is only .004 inch diffrence. My question is is this the cylinder that should go with this piston?
Also, if I put in a high compression piston and bored cylinder, would I have to buy a bigger carb or change the jets or exhaust? How do you know what ratio the piston is (ex. 10 to 1, 12 to 1)? Any help or advice on this would be greatly appreciated. Thanx again.

[samster143]

My advice would be to take the piston and cylinder to a shop FAMILIAR with Wiseco pistons and have it measured by them and see what they say. I think .004" is about right for wiseco's but I am not real sure. Hope to have helped.