Howdy all, new to the forum. Im working on a top end rebuild on this xl800, had a power valve screw back out (wave eaters on order) and the power valve just barely made contact with the rear cylinder (the clean one) that cylinder seems to have fared better the the front cylinder, which has a badly pitted and melted piston, but the head looks good for that cylinder. Assuming a lean condition caused the damage to the front cylinder, and precious damage trashed the head for the rear cylinder. I have a clean used head on the way to replace it. Here are my questions:
1. Pistons show .25 front and .75 rear. Is this difference a problem? Plan to order 2 new aftermarket piston sets, are they all about the same or do you have a brand recommendation?
2. is the Powervalve shown suitable for use with the minor piston contact wear?
3. Can I simply hone the cylinders lightly and stuff in the replacement pistons?
4. How do I check the bottom end and bearings?

Thanks!
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