The Thor models share a common design. The info below is unique for the 80. Please see the Thor page for info that is not found here, including troubleshooting. The Walbro page has detailed info on things like the carburetor function and tune up.
Carburetor – WG-8 main jet size #70 or Polini CP (see user manual section 3.2 for more info)
Ignition system – Polini has no information, part number, or drawing of the ignition system. The Italians occasionally assume pilots know important info by magic or something. My guess is that it probably is the #928.600.001 coil used in the Thor 100.
parts #1 engine & exhaust group
parts #2 starter & cooling group
parts #3 redrive group
parts #4 fuel group
parts #5 major engine groups A
parts #6 major engine groups B
Spark plug – Champion RN2C or (better) BR9EG Note: the user manual does not specify the spark plug gap. 0.9mm should be OK.
User & maintenance manual (includes specifications)