positive negative earth

Hello I am fairly new to the form have owned a 69 750 norton for quite a number of years and have recently purchased a pazon ignition system. This is where I am having trouble and thought someone could help me with. This is most likely an easy question for most but for me not a clue. Negative earth machine or positive earth what does this mean and how do I determine which condition my machine has. Does this mean the machine is either positive or negative ground? Can someone help me with this I have installed the unit but get nothing but a few back fires etc switched leads at pick-up plate in case a mistake was made there however not even a burp so switched it back all the wiring appears to be connected correctly which brings me to a positive or negative earth ? if I have made a mistake here. There is spark at the plugs however the machine will not run just bark once and a while any ideas will be helpful thanks. Doxford

Check with Pazon in case the reverse polarity damaged the unit.
Earth and Ground = same thing. Us English like earth, US uses Ground term! So, positive + batt terminal goes to frame and negative - should disappear into the harness above the battery. I guess you'll know that now.
If you have a spark then the unit is working OK and connections fine. However someone mentioned here a while back that the wires were reversed on the plate on their new Pazon. Are you happy the timing was statically set according to instructions? Does sound like timing is off.

Check your timing. Consult your service manual to find true top dead center. This requires the removal of the rocker covers for valve and piston positioning. If it sparks and back fires at you, the set up may be 90-180 deg. off depending on how you set your timing before the installation.
Cheers.
JD

Found the problem just thought I'd let you know Tks for the help I rechecked the wiring and the timing {TDC} via timing tool{homemade} and everything checks out correct but still the bike will not run only bark here and there. Just didn't make sense have spark, fuel, the bike was running before I changed the ignition to the pazon unit so what gives. So out of desperation I moved the position of the trigger{pick-up plate] on its adjustment to hard over counter clockwise regardless of any instruction and kicked it over Bingo the machine started now I was getting somewhere. To keep the story short I moved the magnetic rotor with the machine set at TDC and adjusted pick-up plate {trigger} once again into position. For some reason I am not knowing why this would not work according to the instructions. I have actually moved the magnetic rotor beyond the set point by about 4 degrees cam and the red dot on the pazon rotor is not in the window at TDC odd however I have managed to find the "spot" and I'm back in the saddle again tks.

You should check the timing with a strobe light through the hole in the primary cover. While Nortons will fire up and run with quite a wide variation in timing, they run much better with it set correctly. I have had a boyer ignition that didn't time properly on static setting, but was fine once I strobed it.