How do you remove piston cylinder to change o ring

They mean if you run it then remove it.

if it has head bolts , the same as any engine
if it doesn't , the cylinder will unbolt at the crankcase
undo those bolts and carefully pull the cylinder off the piston
mark the location of the cylinder so that assembly puts the exhaust and inlet ports in the right places
NOTE-- 2 stroke rings are pegged in the ring groove so when assembling the cylinder back onto the piston , ensure that the ring gaps are at the small peg or you will break the rings when pushing the cylinder down over the piston

there are only four possibilities left:
1: valves are not fully seating - adjust rocker arm / cam
2: piston rings are bad - replace rings
3: holes in pistons - replace
4: cylinders out of round - most complicated repair, bore / machine cylinders and replace piston rings with oversized rings.

of course you could just have 'gunk' on the valves preventing full closure........

Remove the cylinder to expose the piston and rings,the rings should be lose around the piston, they should have a break in them so they can be removed and squeezed in to fit back into the cylinder

What you need to do is lift the car take out the wheel where crank shaft is,
also know as the harmonic balancer

You will have to change the cylinder piston; the ring around the piston is what causing this to misfire. As you can see, every time you remove that one spark plug, to look as liquid is been spill on it. The ring around the piston is damage and the cylinder is not burning the oil and gas as the spark plug send fire into the cylinder. contact your local mechanic for hands on help.

im assuming you mean piston rings. to change your piston rings you need to remove spark plugs, empty your oil, remove your oil pan. unbolt your crank shaft and anything attached to it. at this point you should be able to pull your pistons down remove the rings and put new ones on as per the instructions provided with the new rings. use a hone or at least acid wash the cylinders before you reinstall your pistons. also make sure you reset your timing correctly. goodluck

It can be time consuming and the end result may not be desirable if you haven't done it before.
--- The following is just a sample of what to do once the engine is torn down: Pistons and Connecting Rods

1. Before installing the piston/connecting rod assembly, oil the pistons, piston rings and the cylinder walls with light engine oil. Install connecting rod bolt protectors or rubber hose onto the connecting rod bolts/studs. Also perform the following:
   1. Select the proper ring set for the size cylinder bore.
   2. Position the ring in the bore in which it is going to be used.
   3. Push the ring down into the bore area where normal ring wear is not encountered.
   4. Use the head of the piston to position the ring in the bore so that the ring is square with the cylinder wall. Use caution to avoid damage to the ring or cylinder bore.
   5. Measure the gap between the ends of the ring with a feeler gauge. Ring gap in a worn cylinder is normally greater than specification. If the ring gap is greater than the specified limits, try an oversize ring set. Fig. 5: Checking the piston ring-to-ring groove side clearance using the ring and a feeler gauge
      
      
   6. Check the ring side clearance of the compression rings with a feeler gauge inserted between the ring and its lower land according to specification. The gauge should slide freely around the entire ring circumference without binding. Any wear that occurs will form a step at the inner portion of the lower land. If the lower lands have high steps, the piston should be replaced. Fig. 6: The notch on the side of the bearing cap matches the tang on the bearing insert
      
   
   
2. Unless new pistons are installed, be sure to install the pistons in the cylinders from which they were removed. The numbers on the connecting rod and bearing cap must be on the same side when installed in the cylinder bore. If a connecting rod is ever transposed from one engine or cylinder to another, new bearings should be fitted and the connecting rod should be numbered to correspond with the new cylinder number. The notch on the piston head goes toward the front of the engine.
3. Install all of the rod bearing inserts into the rods and caps. Fig. 7: Most rings are marked to show which side of the ring should face up when installed to the piston
   
   
4. Install the rings to the pistons. Install the oil control ring first, then the second compression ring and finally the top compression ring. Use a piston ring expander tool to aid in installation and to help reduce the chance of breakage. Fig. 8: Install the piston and rod assembly into the block using a ring compressor and the handle of a hammer
   
   
5. Make sure the ring gaps are properly spaced around the circumference of the piston. Fit a piston ring compressor around the piston and slide the piston and connecting rod assembly down into the cylinder bore, pushing it in with the wooden hammer handle. Push the piston down until it is only slightly below the top of the cylinder bore. Guide the connecting rod onto the crankshaft bearing journal carefully, to avoid damaging the crankshaft.
6. Check the bearing clearance of all the rod bearings, fitting them to the crankshaft bearing journals. Follow the procedure in the crankshaft installation above.
7. After the bearings have been fitted, apply a light coating of assembly oil to the journals and bearings.
8. Turn the crankshaft until the appropriate bearing journal is at the bottom of its stroke, then push the piston assembly all the way down until the connecting rod bearing seats on the crankshaft journal. Be careful not to allow the bearing cap screws to strike the crankshaft bearing journals and damage them.
9. After the piston and connecting rod assemblies have been installed, check the connecting rod side clearance on each crankshaft journal.
10. Prime and install the oil pump and the oil pump intake tube.
11. Install the auxiliary/balance shaft(s)/assembly(ies).

OHV Engines CAMSHAFT, LIFTERS AND TIMING ASSEMBLY

1. Install the camshaft.
2. Install the lifters/followers into their bores.
3. Install the timing gears/chain assembly.

CYLINDER HEAD(S)

1. Install the cylinder head(s) using new gaskets.
2. Assemble the rest of the valve train (pushrods and rocker arms and/or shafts).

OHC Engines CYLINDER HEAD(S)

1. Install the cylinder head(s) using new gaskets.
2. Install the timing sprockets/gears and the belt/chain assemblies.

Engine Covers and Components Install the timing cover(s) and oil pan. Refer to your notes and drawings made prior to disassembly and install all of the components that were removed. Install the engine into the vehicle. Engine Start-up and Break-in STARTING THE ENGINE Now that the engine is installed and every wire and hose is properly connected, go back and double check that all coolant and vacuum hoses are connected. Check that your oil drain plug is installed and properly tightened. If not already done, install a new oil filter onto the engine. Fill the crankcase with the proper amount and grade of engine oil. Fill the cooling system with a 50/50 mixture of coolant/water.

1. Connect the vehicle battery.
2. Start the engine. Keep your eye on your oil pressure indicator; if it does not indicate oil pressure within 10 seconds of starting, turn the vehicle OFF. WARNING
   Damage to the engine can result if it is allowed to run with no oil pressure. Check the engine oil level to make sure that it is full. Check for any leaks and if found, repair the leaks before continuing. If there is still no indication of oil pressure, you may need to prime the system.
   
3. Confirm that there are no fluid leaks (oil or other).
4. Allow the engine to reach normal operating temperature (the upper radiator hose will be hot to the touch).
5. At this point any necessary checks or adjustments can be performed, such as ignition timing.
6. Install any remaining components or body panels which were removed.

Take off seat, and tank.
Drain coolant, remove exhaust, remove coil, and ground wire from head.
Remove triangle head stays, and spark plug.
Remove right side power valve cover, and clip and spacer for the power valve arm.
Remove four cylinder nuts.
(If you remove the lower radiator hose that goes between the left and right radiator, you can get the cylinder off without removing the head.)
Use a soft blow, or dead blow hammer to free up the cylinder (Piece of wood)
Use kick starter to get piston low, and carefully remove cylinder upward.
Put a rag around connecting rod, and remove piston pin clip on one side. (So the clip doesn't fall into engine) Then push the pin out and remove the piston.
Note, you will have a mark on the left side of the cylinder of "A" or "B" for a stock piston, but Wiseco's don't use this.
Use caution when putting on the new ring, and getting the cylinder onto it as not to twist the cylinder because it will "catch" the end of the ring and do damage.

Remove your exhaust manifold. Look into the cylinder with a flash light. You are looking for scratches. Anything larger then a light fingernail is definite proof you need a new cylinder/piston assy.

If it passes that test do the following:

Pour mixed fuel straight into your cylinder until 1/4 full. Slowly pull your saw over while looking into the cylinder. If you see bubbles after the ring/rings go by then you need a new cylinder/piston assy. On rare occasions if no scratches are present on the cylinder wall or piston, you may be able to change just the rings.