Most modern 2 stroke engines do not use any sort of iron liner, so there is nothing to break the glaze on. Carefully remove any aluminum that may have transfered to the cylinder wall from the piston. I use an old pocket knife for this task. If the liner is tore up, little can be done to help it out. Long/deep scratches are the worst, they will bleed off compression and effect sealing as the piston moves past the ports in the jug. Keep in mind that the piston acts like a valve as it moves in the bore, covering and uncovering ports along the way.
The cylinder walls are coated or plated very thin with whatever proprietary method and alloy each manufacture happens to use. The material is extremely hard, which makes it resist wear, and scratching from abrasives that enter the engine, etc.
In almost all cases, nothing more is needed for bore preparation than making sure you remove any and all transfered material from the piston. It doesn't seem to hurt anything to give the bore a very light buffing with a peice of 600 or finer grit autobody sandpaper. Even doing this I would use extreme care not to remove any material.
Because of the transfers and other porting inside the jug, they can be difficult to hone as Brad mentions. I'm not even sure honing them is a good idea, and I certainly wouldn't use any coarse grit stones for this task.
In attempts to save jugs that have some minor damage, scratches, etc, we have taken a peice of 600 grit paper and carefully wrapped a the stone brake hone with it. Then used a drill to quickly clean up the cylinder wall. If the sandpaper is effectively attached to the stones and wound counterclockwise on the hone, it will clean up the bore with a couple of quick stokes with a battery powered drill.
Make sure to give the jug a good cleaning with carburetor or brake parts cleaner, and wipe it dry with a clean cloth, making sure no small abrasive particles are left in the jug from the honing process......Cliff
