Did you do engine adjustments before or after engine break-in?Far as it hard pulling the pull start.
Sounds like it may be some what flooded.Take out the glow plug,and pull start it about 20-30 times.

That will help with the flooding problem.Make sure your throttle trim is in the neuteral position.
Then take off you airfilter and look down the opening.It should be open about 1/16.