Motorcycle Repair: LT 80 atv weak fire, lt 80, suzuki atv

Question
I'm just getting started in atv repair/resale so forgive me if this is basic stuff.  I just aquired an '87 LT 80 suzuki atv that has extremely weak fire.  After a series of uneducated guesses, I found that there is a direct short in the lower coil on the magneto while the upper coil has a resistance of 170 ohms.  Where could I find out what the proper resistance would be for those coils and how much V-A/C the magneto should be sending to the coil while the motor is turning?

Thank you for your time,
In His service,
David Thompson

Answer
around 6 volts. that system may be weak at kick over speeds but as soon as it hits 1000 rpm they come alive. remove the flywheel, sand it smooth inside, sand ends of the arms, check grounds. if it has any spark, with a new plug it should run, some of the mopeds have such slight spark you hardly know its there.