So you can count to 3 or 4 between every time is misses at 3,000 rpm.  New plugs made no difference.  Bad news:  checked the compression: over 120 on right side   under 70 on the left.  So either I have a valve that isn't closing or more likely a burned exhaust valve.

Before I start to pull it apart does any one have any suggestions on further things to check first?  If you have had this problem what did you end up doing?

Is the valve lash correct?

Just got tank drained and pulled off.  Will check the valve clearance in the next day or so.

Is there anything else that might cause this?