When you adjusted the valves, did you look to see if the compression release was working? I do valve adjustments the same way ILengine does with one change. After each adjustment, I rotate the engine through three complete cycles and then recheck each gap again until I get the proper reading twice in a row. Only then do I go to the other valve. While doing this I watch the action of both valves to make sure that I see the exhaust valve open slightly before each compression stroke. By doing this, I can make sure that the compression release is working and that I get the proper gap on each valve. The one thing that ILengine did not say, but I think he assumed, that you must make sure that you do the adjustment slightly passed TDC on the compression stroke only. If the valves are out of adjustment, both valves could be closed between the intake and exhaust strokes. Finally, does the engine turn over smoothly, using the starter, with the spark plug removed?