So what yall think, does this look like 5000 miles? Because thats when the previous owner said he put in the 351 kit

Because i heard air inthe crankcase during the leakdown i need to take a look at the rings... But i cant seem to get the cylinder off! Any tips?

 

Your pics indicate a good deal of carbon but perhaps not necessarily odd based on the fueling issues you reported earlier. Your piston skirt and rings may be more telling. Have you tried pouring a little solvent or other thin fluid into the valve pockets to see if there's an obvious tweaked valve. Sometimes it's not as evident as you might think. I'm a little su****ious of the intake valve with the wet residue all around the circumference. Did you spill any oil/fluids into the combustion chamber when removing and tilting the head?

 

The residue on the valves is just oil from handling it when i took the head off. I did put some ATF on the valve seats and this morning saw leakage into the exhaust. Intake valves look good. I'll probably clean the head off a bit and drop it with a machine shop to inspect/repair the seats or valves. I'm not interested in getting/making the tools to pull the valves.

Is it odd that theres so much clearance between the piston and cylinder, and that the piston is sitting a little offset in the bore -- eg, not concentric?

Got the cylinder off, honing looks pretty good. Here's a pic of the piston. Surface between the rings looks pretty good so I imagine theyre doing their job. Honestly i was hoping for botched rings because I could definitely hear a lot of airflow in the crankcase during the leakdown test. Was listening through the port where you look for TDC marks
No scoring on the piston but there is a little wear spot below my finger which is reflected in the cylinder. I'll try to get some better pics after work.

 

here are some more pics of the wearing on the cylinder and piston

 

You found the piston, now put it back together and fix the carb!

 

i dunno man, the carb was just rebuilt by Bill Blue and the valves are leaking. funny though

 

If you had fluid flow in your test with the valves seated, you've got an issue going on with the valves/seats. Does make you wonder about the alleged mileage on the engine per the previous owner. Hard to tell anything definitive over internet pics and without doing some actual mechanical measurements, but those cross-hatch hone marks look quite good.

 

been a while but i got the bike back together and have put a hundred miles on it. its now working great -- idles consistently at 1500, doesn't hang idle, doesn't stall at idle, doesnt feel rich at altitude, and fuel economy went from 35mpg to 55+mpg

i ended up bead blasting and remachining the head, replacing both exhaust valves. changed out rings and had the cylinder inspected. reset valve clearances.... it think it was mostly the valves. and no, durielk, i didn't do anything different with the carb

thanks for your help folks!!