[alanmcorcoran]

Re running rough: There doesn't seem to be a foolproof way of determining what causes this, but, here's a few:

1) Carb needs cleaning. Easy: run carb cleaner (berrymans or Seafoam) through Better: Actually clean the carb.
2) Valves need adjusting. Not recommended for non-mechanics - take to a shop.
3) Emissions (if in CA) needs cleaning.
4) Gas is old/bad.
5) Plug is fouled.
6) Gas Filter is clogged.
7) Air Filter is clogged. (Easy: remove, inspect, clean or replace.
8) Hoses are loose or not connected.
9) Cap on drain to aire filter box is missing.

Enjoy!