It would be easy to determine which is causing the issue with a simple in-line spark tester, There are many styles and this is one of four styles I use;
From your description I'd lean toward ignition as well, If it is "skipping" it will run rich from not being able to burn the fuel in the "skipping" cylinder.
Check with your local dealers and see if they have a spark tester, We keep them in stock.....
Originally Posted by piston slapper
You never learn anything until you admit you don't know it all...
"Why go out preserved when you can go out beat up, worn out, sliding in sideways screaming, Holy Sh!t What A Ride" !!!